apps/nshlib
^^^^^^^^^^^
This directory contains the NuttShell (NSH) library. This library can be
linked with other logic to provide a simple shell application for NuttX.
- Console/NSH Front End
- Command Overview
- Conditional Command Execution
- Looping
- Built-In Variables
- Current Working Directory
Environment Variables
- NSH Start-Up Script
- Simple Commands
- Built-In Applications
- NSH Configuration Settings
Command Dependencies on Configuration Settings
Built-in Application Configuration Settings
NSH-Specific Configuration Settings
- Common Problems
Console/NSH Front End
^^^^^^^^^^^^^^^^^^^^^
Using settings in the configuration file, NSH may be configured to
use either the serial stdin/out or a telnet connection as the console
or BOTH. When NSH is started, you will see the following welcome on
either console:
NuttShell (NSH)
nsh>
'nsh>' is the NSH prompt and indicates that you may enter a command
from the console.
Command Overview
^^^^^^^^^^^^^^^^
This directory contains the NuttShell (NSH). This is a simple
shell-like application. At present, NSH supports the following commands
forms:
Simple command: <cmd>
Command with re-directed output: <cmd> > <file>
<cmd> >> <file>
Background command: <cmd> &
Re-directed background command: <cmd> > <file> &
<cmd> >> <file> &
Where:
<cmd> is any one of the simple commands listed later.
<file> is the full or relative path to any writeable object
in the file system name space (file or character driver).
Such objects will be referred to simply as files throughout
this README.
NSH executes at the mid-priority (128). Backgrounded commands can
be made to execute at higher or lower priorities using nice:
[nice [-d <niceness>>]] <cmd> [> <file>|>> <file>] [&]
Where <niceness> is any value between -20 and 19 where lower
(more negative values) correspond to higher priorities. The
default niceness is 10.
Multiple commands per line. NSH will accept multiple commands per
command line with each command separated with the semi-colon character (;).
If CONFIG_NSH_CMDPARMS is selected, then the output from commands, from
file applications, and from NSH built-in commands can be used as arguments
to other commands. The entity to be executed is identified by enclosing
the command line in back quotes. For example,
set FOO `myprogram $BAR`
Will execute the program named myprogram passing it the value of the
environment variable BAR. The value of the environment variable FOO
is then set output of myprogram on stdout. Because this feature commits
significant resources, it is disabled by default.
If CONFIG_NSH_ARGCAT is selected, the support concatenation of strings
with environment variables or command output. For example:
set FOO XYZ
set BAR 123
set FOOBAR ABC_${FOO}_${BAR}
would set the environment variable FOO to XYZ, BAR to 123 and FOOBAR
to ABC_XYZ_123. If NSH_ARGCAT is not selected, then a slightly small
FLASH footprint results but then also only simple environment
variables like $FOO can be used on the command line.
CONFIG_NSH_QUOTE enables back-slash quoting of certain characters within
the command. This option is useful for the case where an NSH script is
used to dynamically generate a new NSH script. In that case, commands
must be treated as simple text strings without interpretation of any
special characters. Special characters such as $, `, ", and others must
be retained intact as part of the test string. This option is currently
only available is CONFIG_NSH_ARGCAT is also selected.
Conditional Command Execution
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
An if-then[-else]-fi construct is also supported in order to
support conditional execution of commands. This works from the
command line but is primarily intended for use within NSH scripts
(see the sh command). The syntax is as follows:
if [!] <cmd>
then
[sequence of <cmd>]
else
[sequence of <cmd>]
fi
Looping
^^^^^^^
while-do-done and until-do-done looping constructs are also supported.
These works from the command line but are primarily intended for use
within NSH scripts (see the sh command). The syntax is as follows:
while <test-cmd>; do <cmd-sequence>; done
Execute <cmd-sequence> as long as <test-cmd> has an exit status of
zero.
until <test-cmd>; do <cmd-sequence>; done
Execute <cmd-sequence> as long as <test-cmd> has a non-zero exit
status.
A break command is also supported. The break command is only meaningful
within the body of the a while or until loop, between the do and done
tokens. If the break command is executed within the body of a loop, the
loop will immediately terminate and execution will continue with the
next command immediately following the done token.
Built-In Variables
^^^^^^^^^^^^^^^^^^
$? - The result of the last simple command execution
Current Working Directory
^^^^^^^^^^^^^^^^^^^^^^^^^
All path arguments to commands may be either an absolute path or a
path relative to the current working directory. The current working
directory is set using the 'cd' command and can be queried either
by using the 'pwd' command or by using the 'echo $PWD' command.
Environment Variables:
----------------------
PWD - The current working directory
OLDPWD - The previous working directory
NSH Start-Up Script
^^^^^^^^^^^^^^^^^^^
NSH supports options to provide a start up script for NSH. In general
this capability is enabled with CONFIG_NSH_ROMFSETC, but has
several other related configuration options as described in the final
section of this README. This capability also depends on:
- CONFIG_DISABLE_MOUNTPOINT not set
- CONFIG_NFILE_DESCRIPTORS > 4
- CONFIG_FS_ROMFS
Default Start-Up Behavior
-------------------------
The implementation that is provided is intended to provide great flexibility
for the use of Start-Up files. This paragraph will discuss the general
behavior when all of the configuration options are set to the default
values.
In this default case, enabling CONFIG_NSH_ROMFSETC will cause
NSH to behave as follows at NSH startup time:
- NSH will create a read-only RAM disk (a ROM disk), containing a tiny
ROMFS file system containing the following:
|--init.d/
`-- rcS
Where rcS is the NSH start-up script
- NSH will then mount the ROMFS file system at /etc, resulting in:
|--dev/
| `-- ram0
`--etc/
`--init.d/
`-- rcS
- By default, the contents of rcS script are:
# Create a RAMDISK and mount it at XXXRDMOUNTPOINTXXX
mkrd -m 1 -s 512 1024
mkfatfs /dev/ram1
mount -t vfat /dev/ram1 /tmp
- NSH will execute the script at /etc/init.d/rcS at start-up (before the
first NSH prompt. After execution of the script, the root FS will look
like:
|--dev/
| |-- ram0
| `-- ram1
|--etc/
| `--init.d/
| `-- rcS
`--tmp/
Modifying the ROMFS Image
-------------------------
The contents of the /etc directory are retained in the file
apps/nshlib/nsh_romfsimg.h (OR, if CONFIG_NSH_ARCHROMFS
is defined, include/arch/board/rcS.template). In order to modify
the start-up behavior, there are three things to study:
1. Configuration Options.
The additional CONFIG_NSH_ROMFSETC configuration options
discussed in the final section of this README.
2. tools/mkromfsimg.sh Script.
The script tools/mkromfsimg.sh creates nsh_romfsimg.h.
It is not automatically executed. If you want to change the
configuration settings associated with creating and mounting
the /tmp directory, then it will be necessary to re-generate
this header file using the mkromfsimg.sh script.
The behavior of this script depends upon three things:
- The configuration settings of the installed NuttX configuration.
- The genromfs tool (available from http://romfs.sourceforge.net).
- The file apps/nshlib/rcS.template (OR, if
CONFIG_NSH_ARCHROMFS is defined, include/arch/board/rcs.template)
3. rcS.template.
The file apps/nshlib/rcS.template contains the general form
of the rcS file; configured values are plugged into this
template file to produce the final rcS file.
NOTE:
apps/nshlib/rcS.template generates the standard, default
nsh_romfsimg.h file. If CONFIG_NSH_ARCHROMFS is defined
in the NuttX configuration file, then a custom, board-specific
nsh_romfsimg.h file residing in boards/<arch>/<chip>/<board>/include
will be used. NOTE when the OS is configured, include/arch/board will
be linked to boards/<arch>/<chip>/<board>/include.
All of the startup-behavior is contained in rcS.template. The
role of mkromfsimg.sh is to (1) apply the specific configuration
settings to rcS.template to create the final rcS, and (2) to
generate the header file nsh_romfsimg.h containing the ROMFS
file system image.
Simple Commands
^^^^^^^^^^^^^^^
o [ <expression> ]
o test <expression>
These are two alternative forms of the same command. They support
evaluation of a boolean expression which sets $?. This command
is used most frequently as the conditional command following the
'if' in the if-then[-else]-fi construct.
Expression Syntax:
------------------
expression = simple-expression | !expression |
expression -o expression | expression -a expression
simple-expression = unary-expression | binary-expression
unary-expression = string-unary | file-unary
string-unary = -n string | -z string
file-unary = -b file | -c file | -d file | -e file | -f file |
-r file | -s file | -w file
binary-expression = string-binary | numeric-binary
string-binary = string = string | string == string | string != string
numeric-binary = integer -eq integer | integer -ge integer |
integer -gt integer | integer -le integer |
integer -lt integer | integer -ne integer
o addroute <target> [<netmask>] <router>
addroute default <ipaddr> <interface>
This command adds an entry in the routing table. The new entry
will map the IP address of a router on a local network(<router>)
to an external network characterized by the <target> IP address and
a network mask <netmask>
The netmask may also be expressed using IPv4 CIDR or IPv6 slash
notation. In that case, the netmask need not be provided.
Example:
nsh> addroute 11.0.0.0 255.255.255.0 10.0.0.2
which is equivalent to
nsh> addroute 11.0.0.0/24 10.0.0.2
The second form of the addroute command can be used to set the default
gateway.
o arp [-t|-a <ipaddr>|-d <ipaddr>|-s <ipaddr> <hwaddr>]
Access the OS ARP table.
-a <ipaddr>
Will show the hardware address that the IP address <ipaddr> is mapped to.
-d <ipaddr>
Will delete the mapping for the IP address <ipaddr> from the ARP table.
-s <ipaddr> <hwaddr>
Will set (or replace) the mapping of the IP address <ipaddr> to the
hardware address <hwaddr>.
-t
Will dump the entire content of the ARP table. This option is only
available if CONFIG_NETLINK_ROUTE is enabled.
Example:
nsh> arp -a 10.0.0.1
nsh: arp: no such ARP entry: 10.0.0.1
nsh> arp -s 10.0.0.1 00:13:3b:12:73:e6
nsh> arp -a 10.0.0.1
HWAddr: 00:13:3b:12:73:e6
nsh> arp -d 10.0.0.1
nsh> arp -a 10.0.0.1
nsh: arp: no such ARP entry: 10.0.0.1
o base64dec [-w] [-f] <string or filepath>
o base64dec [-w] [-f] <string or filepath>
o basename <path> [<suffix>]
Extract the final string from a <path> by removing the preceding path
segments and (optionally) removing any trailing <suffix>.
o break
The break command is only meaningful within the body of the a while or
until loop, between the do and done tokens. Outside of a loop, break
command does nothing. If the break command is executed within the body
of a loop, the loop will immediately terminate and execution will
continue with the next command immediately following the done token.
o cat <path> [<path> [<path> ...]]
This command copies and concatenates all of the files at <path>
to the console (or to another file if the output is redirected).
o cd [<dir-path>|-|~|..]
Changes the current working directory (PWD). Also sets the
previous working directory environment variable (OLDPWD).
FORMS:
------
'cd <dir-path>' sets the current working directory to <dir-path>.
'cd -' sets the current working directory to the previous
working directory ($OLDPWD). Equivalent to 'cd $OLDPWD'.
'cd' or 'cd ~' set the current working directory to the 'home'
directory. The 'home' directory can be configured by setting
CONFIG_LIB_HOMEDIR in the configuration file. The default
'home' directory is '/'.
'cd ..' sets the current working directory to the parent directory.
o cmp <path1> <path2>
Compare of the contents of the file at <file1> with the contents of
the file at <path2>. Returns an indication only if the files differ.
o cp <source-path> <dest-path>
Copy of the contents of the file at <source-path> to the location
in the file system indicated by <path-path>
o date [-s "MMM DD HH:MM:SS YYYY"]
Show or set the current date and time.
Only one format is used both on display and when setting the date/time:
MMM DD HH:MM:SS YYYY. For example,
data -s "Sep 1 11:30:00 2011"
24-hour time format is assumed.
o dd if=<infile> of=<outfile> [bs=<sectsize>] [count=<sectors>] [skip=<sectors>]
Copy blocks from <infile> to <outfile>. <nfile> or <outfile> may
be the path to a standard file, a character device, or a block device.
Examples:
1. Read from character device, write to regular file. This will
create a new file of the specified size filled with zero.
nsh> dd if=/dev/zero of=/tmp/zeros bs=64 count=16
nsh> ls -l /tmp
/tmp:
-rw-rw-rw- 1024 ZEROS
2. Read from character device, write to block device. This will
fill the entire block device with zeros.
nsh> ls -l /dev
/dev:
brw-rw-rw- 0 ram0
crw-rw-rw- 0 zero
nsh> dd if=/dev/zero of=/dev/ram0
3. Read from a block device, write to a character device. This
will read the entire block device and dump the contents in
the bit bucket.
nsh> ls -l /dev
/dev:
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
nsh> dd if=/dev/ram0 of=/dev/null
o delroute <target> [<netmask>]
This command removes an entry from the routing table. The entry
removed will be the first entry in the routing table that matches
the external network characterized by the <target> IP address and
the network mask <netmask>
The netmask may also be expressed using IPv4 CIDR or IPv6 slash
notation. In that case, the netmask need not be provided.
Example:
nsh> delroute 11.0.0.0 255.255.255.0
which is equivalent to
nsh> delroute 11.0.0.0/24
o df
Show the state of each mounted volume.
Example:
nsh> mount
/etc type romfs
/tmp type vfat
nsh> df
Block Number
Size Blocks Used Available Mounted on
64 6 6 0 /etc
512 985 2 983 /tmp
nsh>
o dirname <path>
Extract the path string leading up to the full <path> by removing
the final directory or file name.
o dmesg
This command can be used to dump (and clear) the content of any
buffered syslog output messages. This command is only available
if CONFIG_RAMLOG_SYSLOG is enabled. In that case, syslog output
will be collected in an in-memory, circular buffer. Entering the
'dmesg' command will dump the content of that in-memory, circular
buffer to the NSH console output. 'dmesg' has the side effectof
clearing the buffered data so that entering 'dmesg' again will
show only newly buffered data.
o echo [-n] [<string|$name> [<string|$name>...]]
Copy the sequence of strings and expanded environment variables to
console out (or to a file if the output is re-directed).
The -n option will suppress the trailing newline character.
o env
Show the current name-value pairs in the environment. Example:
nsh> env
PATH=/bin
nsh> set foo bar
nsh> env
PATH=/bin
foo=bar
nsh> unset PATH
nsh> env
foo=bar
nsh>
NOTE: NSH variables are *not* shown by the env command.
o exec <hex-address>
Execute the user logic at address <hex-address>. NSH will pause
until the execution unless the user logic is executed in background
via 'exec <hex-address> &'
o exit
Exit NSH. Only useful if you have started some other tasks (perhaps
using the 'exec' command') and you would like to have NSH out of the
way.
o export <name> [<value>]
The 'export' command sets an environment variable, or promotes an
NSH variable to an environment variable. As examples:
1. Using 'export' to promote an NSH variable to an environment variable.
nsh> env
PATH=/bin
nsh> set foo bar
nsh> env
PATH=/bin
nsh> export foo
nsh> env
PATH=/bin
foo=bar
A group-wide environment variable is created with the same value as the
local NSH variable; the local NSH variable is removed.
NOTE: This behavior differs from the Bash shell. Bash will retain the
local Bash variable which will shadow the environment variable of the
same name and same value.
2. Using 'export' to set an environment variable
nsh> export dog poop
nsh> env
PATH=/bin
foo=bar
dog=poop
The export command is not supported by NSH unless both CONFIG_NSH_VARS=y
and CONFIG_DISABLE_ENVIRON is not set.
o free
Show the current state of the memory allocator. For example,
nsh> free
free
total used free largest
Mem: 4194288 1591552 2602736 2601584
Where:
total - This is the total size of memory allocated for use
by malloc in bytes.
used - This is the total size of memory occupied by
chunks handed out by malloc.
free - This is the total size of memory occupied by
free (not in use) chunks.
largest - Size of the largest free (not in use) chunk
o get [-b|-n] [-f <local-path>] -h <ip-address> <remote-path>
Use TFTP to copy the file at <remote-address> from the host whose IP
address is identified by <ip-address>. Other options:
-f <local-path>
The file will be saved relative to the current working directory
unless <local-path> is provided.
-b|-n
Selects either binary ("octet") or test ("netascii") transfer
mode. Default: text.
o help [-v] [<cmd>]
Presents summary information about NSH commands to console. Options:
-v
Show verbose output will full command usage
<cmd>
Show full command usage only for this command
o hexdump <file or device>
Dump data in hexadecimal format from a file or character device.
o ifconfig [nic_name [<ip-address>|dhcp]] [dr|gw|gateway <dr-address>] [netmask <net-mask>] [dns <dns-address>] [hw <hw-mac>]
Show the current configuration of the network, for example:
nsh> ifconfig
eth0 HWaddr 00:18:11:80:10:06
IPaddr:10.0.0.2 DRaddr:10.0.0.1 Mask:255.255.255.0
if networking statistics are enabled (CONFIG_NET_STATISTICS), then
this command will also show the detailed state of transfers by protocol.
NOTE: This commands depends upon having the procfs file system configured
into the system. The procfs file system must also have been mounted
with a command like:
nsh> mount -t procfs /proc
o ifdown <interface>
Take down the interface identified by the name <interface>.
Example:
ifdown eth0
o ifup <interface>
Bring up down the interface identified by the name <interface>.
Example:
ifup eth0
o insmod <file-path> <module-name>
Install the loadable OS module at <file-path> as module <module-name>
Example:
nsh> ls -l /mnt/romfs
/mnt/romfs:
dr-xr-xr-x 0 .
-r-xr-xr-x 9153 chardev
nsh> ls -l /dev
/dev:
crw-rw-rw- 0 console
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
crw-rw-rw- 0 ttyS0
nsh> insmod /mnt/romfs/chardev mydriver
nsh> ls -l /dev
/dev:
crw-rw-rw- 0 chardev
crw-rw-rw- 0 console
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
crw-rw-rw- 0 ttyS0
nsh> lsmod
NAME INIT UNINIT ARG TEXT SIZE DATA SIZE
mydriver 20404659 20404625 0 20404580 552 204047a8 0
o irqinfo
Show the current count of interrupts taken on all attached interrupts.
Example:
nsh> irqinfo
IRQ HANDLER ARGUMENT COUNT RATE
3 00001b3d 00000000 156 19.122
15 0000800d 00000000 817 100.000
30 00000fd5 20000018 20 2.490
o kill -<signal> <pid>
Send the <signal> to the task identified by <pid>.
o losetup [-d <dev-path>] | [[-o <offset>] [-r] <ldev-path> <file-path>]
Setup or teardown the loop device:
1. Teardown the setup for the loop device at <dev-path>:
losetup d <dev-path>
2. Setup the loop device at <dev-path> to access the file at <file-path>
as a block device:
losetup [-o <offset>] [-r] <dev-path> <file-path>
Example:
nsh> dd if=/dev/zero of=/tmp/image bs=512 count=512
nsh> ls -l /tmp
/tmp:
-rw-rw-rw- 262144 IMAGE
nsh> losetup /dev/loop0 /tmp/image
nsh> ls -l /dev
/dev:
brw-rw-rw- 0 loop0
nsh> mkfatfs /dev/loop0
nsh> mount -t vfat /dev/loop0 /mnt/example
nsh> ls -l /mnt
ls -l /mnt
/mnt:
drw-rw-rw- 0 example/
nsh> echo "This is a test" >/mnt/example/atest.txt
nsh> ls -l /mnt/example
/mnt/example:
-rw-rw-rw- 16 ATEST.TXT
nsh> cat /mnt/example/atest.txt
This is a test
nsh>
o ln [-s] <target> <link>
The link command will create a new symbolic link at <link> for the
existing file or directory, <target>. This implementation is simplied
for use with NuttX in these ways:
- Links may be created only within the NuttX top-level, pseudo file
system. No file system currently supported by NuttX provides
symbolic links.
- For the same reason, only soft links are implemented.
- File privileges are ignored.
- c_time is not updated.
o ls [-lRs] <dir-path>
Show the contents of the directory at <dir-path>. NOTE:
<dir-path> must refer to a directory and no other file system
object.
Options:
--------
-R Show the constents of specified directory and all of its
sub-directories.
-s Show the size of the files along with the filenames in the
listing
-l Show size and mode information along with the filenames
in the listing.
o lsmod
Show information about the currently installed OS modules. This information includes:
- The module name assigned to the module when it was installed (NAME, string).
- The address of the module initialization function (INIT, hexadecimal).
- The address of the module un-initialization function (UNINIT, hexadecimal).
- An argument that will be passed to the module un-initialization function (ARG, hexadecimal).
- The start of the .text memory region (TEXT, hexadecimal).
- The size of the .text memory region size (SIZE, decimal).
- The start of the .bss/.data memory region (DATA, hexadecimal).
- The size of the .bss/.data memory region size (SIZE, decimal).
Example:
nsh> lsmod
NAME INIT UNINIT ARG TEXT SIZE DATA SIZE
mydriver 20404659 20404625 0 20404580 552 204047a8 0
o md5 [-f] <string or filepath>
o mb <hex-address>[=<hex-value>][ <hex-byte-count>]
o mh <hex-address>[=<hex-value>][ <hex-byte-count>]
o mw <hex-address>[=<hex-value>][ <hex-byte-count>]
Access memory using byte size access (mb), 16-bit accesses (mh),
or 32-bit access (mw). In each case,
<hex-address>. Specifies the address to be accessed. The current
value at that address will always be read and displayed.
<hex-address>=<hex-value>. Read the value, then write <hex-value>
to the location.
<hex-byte-count>. Perform the mb, mh, or mw operation on a total
of <hex-byte-count> bytes, increment the <hex-address> appropriately
after each access
Example
nsh> mh 0 16
0 = 0x0c1e
2 = 0x0100
4 = 0x0c1e
6 = 0x0110
8 = 0x0c1e
a = 0x0120
c = 0x0c1e
e = 0x0130
10 = 0x0c1e
12 = 0x0140
14 = 0x0c1e
nsh>
o mkdir <path>
Create the directory at <path>. All components of of <path>
except the final directory name must exist on a mounted file
system; the final directory must not.
Recall that NuttX uses a pseudo file system for its root file system.
The mkdir command can only be used to create directories in volumes
set up with the mount command; it cannot be used to create directories
in the pseudo file system.
Example:
^^^^^^^^
nsh> mkdir /mnt/fs/tmp
nsh> ls -l /mnt/fs
/mnt/fs:
drw-rw-rw- 0 TESTDIR/
drw-rw-rw- 0 TMP/
nsh>
o mkfatfs [-F <fatsize>] [-r <rootdirentries>] <block-driver>
Format a fat file system on the block device specified by <block-driver>
path. The FAT size may be provided as an option. Without the <fatsize>
option, mkfatfs will select either the FAT12 or FAT16 format. For
historical reasons, if you want the FAT32 format, it must be explicitly
specified on the command line.
The -r option may be specified to select the the number of entries in
the root directory. Typical values for small volumes would be 112 or 224;
512 should be used for large volumes, such as hard disks or very large
SD cards. The default is 512 entries in all cases.
The reported number of root directory entries used with FAT32 is zero
because the FAT32 root directory is a cluster chain.
NSH provides this command to access the mkfatfs() NuttX API.
This block device must reside in the NuttX pseudo file system and
must have been created by some call to register_blockdriver() (see
include/nuttx/fs/fs.h).
o mkfifo <path>
Creates a FIFO character device anywhere in the pseudo file system,
creating whatever pseudo directories that may be needed to complete
the full path. By convention, however, device drivers are place in
the standard /dev directory. After it is created, the FIFO device
may be used as any other device driver. NSH provides this command
to access the mkfifo() NuttX API.
Example:
^^^^^^^^
nsh> ls -l /dev
/dev:
crw-rw-rw- 0 console
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
nsh> mkfifo /dev/fifo
nsh> ls -l /dev
ls -l /dev
/dev:
crw-rw-rw- 0 console
crw-rw-rw- 0 fifo
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
nsh>
o mkrd [-m <minor>] [-s <sector-size>] <nsectors>
Create a ramdisk consisting of <nsectors>, each of size
<sector-size> (or 512 bytes if <sector-size> is not specified).
The ramdisk will be registered as /dev/ram<minor>. If <minor> is
not specified, mkrd will attempt to register the ramdisk as
/dev/ram0.
Example:
^^^^^^^^
nsh> ls /dev
/dev:
console
null
ttyS0
ttyS1
nsh> mkrd 1024
nsh> ls /dev
/dev:
console
null
ram0
ttyS0
ttyS1
nsh>
Once the ramdisk has been created, it may be formatted using
the mkfatfs command and mounted using the mount command.
Example:
^^^^^^^^
nsh> mkrd 1024
nsh> mkfatfs /dev/ram0
nsh> mount -t vfat /dev/ram0 /tmp
nsh> ls /tmp
/tmp:
nsh>
o mount [-t <fstype> [-o <options>] <block-device> <dir-path>]
The mount command performs one of two different operations. If no
parameters are provided on the command line after the mount command,
then the 'mount' command will enumerate all of the current
mountpoints on the console.
If the mount parameters are provied on the command after the 'mount'
command, then the 'mount' command will mount a file system in the
NuttX pseudo-file system. 'mount' performs a three way association,
binding:
File system. The '-t <fstype>' option identifies the type of
file system that has been formatted on the <block-device>. As
of this writing, vfat is the only supported value for <fstype>
Block Device. The <block-device> argument is the full or relative
path to a block driver inode in the pseudo file system. By convention,
this is a name under the /dev sub-directory. This <block-device>
must have been previously formatted with the same file system
type as specified by <fstype>
Mount Point. The mount point is the location in the pseudo file
system where the mounted volume will appear. This mount point
can only reside in the NuttX pseudo file system. By convention, this
mount point is a subdirectory under /mnt. The mount command will
create whatever pseudo directories that may be needed to complete
the full path but the full path must not already exist.
After the volume has been mounted in the NuttX pseudo file
system, it may be access in the same way as other objects in the
file system.
Examples:
^^^^^^^^^
nsh> ls -l /dev
/dev:
crw-rw-rw- 0 console
crw-rw-rw- 0 null
brw-rw-rw- 0 ram0
nsh> ls /mnt
nsh: ls: no such directory: /mnt
nsh> mount -t vfat /dev/ram0 /mnt/fs
nsh> ls -l /mnt/fs/testdir
/mnt/fs/testdir:
-rw-rw-rw- 15 TESTFILE.TXT
nsh> echo "This is a test" >/mnt/fs/testdir/example.txt
nsh> ls -l /mnt/fs/testdir
/mnt/fs/testdir:
-rw-rw-rw- 15 TESTFILE.TXT
-rw-rw-rw- 16 EXAMPLE.TXT
nsh> cat /mnt/fs/testdir/example.txt
This is a test
nsh>
nsh> mount
/etc type romfs
/tmp type vfat
/mnt/fs type vfat
o mv <old-path> <new-path>
Rename the file object at <old-path> to <new-path>. Both paths must
reside in the same mounted file system.
o nfsmount <server-address> <mount-point> <remote-path>
Mount the remote NFS server directory <remote-path> at <mount-point> on the target machine.
<server-address> is the IP address of the remote server.
o nslookup <host-name>
Lookup and print the IP address associated with <host-name>
o passwd <username> <password>
Set the password for the existing user <username> to <password>
o pmconfig [stay|relax] [normal|idle|standby|sleep]
Control power management subsystem.
o poweroff [<n>]
Shutdown and power off the system. This command depends on board-
specific hardware support to power down the system. The optional,
decimal numeric argument <n> may be included to provide power off
mode to board-specific power off logic.
NOTE: Supporting both the poweroff and shutdown commands is redundant.
o ps
Show the currently active threads and tasks. For example,
nsh> ps
PID PRI POLICY TYPE NPX STATE EVENT SIGMASK COMMAND
0 0 FIFO Kthread --- Ready 00000000 Idle Task
1 128 RR Task --- Running 00000000 init
2 128 FIFO Task --- Waiting Semaphore 00000000 nsh_telnetmain()
3 100 RR pthread --- Waiting Semaphore 00000000 <pthread>(21)
nsh>
NOTE: This commands depends upon having the procfs file system configured
into the system. The procfs file system must also have been mounted
with a command like:
nsh> mount -t procfs /proc
o put [-b|-n] [-f <remote-path>] -h <ip-address> <local-path>
Copy the file at <local-address> to the host whose IP address is
identified by <ip-address>. Other options:
-f <remote-path>
The file will be saved with the same name on the host unless
unless <local-path> is provided.
-b|-n
Selects either binary ("octet") or test ("netascii") transfer
mode. Default: text.
o pwd
Show the current working directory.
nsh> cd /dev
nsh> pwd
/dev
nsh>
Same as 'echo $PWD'
nsh> echo $PWD
/dev
nsh>
o readlink <link>
Show target of a soft link.
o reboot [<n>]
Reset and reboot the system immediately. This command depends on hardware
support to reset the system. The optional, decimal numeric argument <n>
may be included to provide reboot mode to board-specific reboot
logic.
NOTE: Supporting both the reboot and shutdown commands is redundant.
o rm <file-path>
Remove the specified <file-path> name from the mounted file system.
Recall that NuttX uses a pseudo file system for its root file system.
The rm command can only be used to remove (unlink) files in volumes
set up with the mount command; it cannot be used to remove names from
the pseudo file system.
Example:
^^^^^^^^
nsh> ls /mnt/fs/testdir
/mnt/fs/testdir:
TESTFILE.TXT
EXAMPLE.TXT
nsh> rm /mnt/fs/testdir/example.txt
nsh> ls /mnt/fs/testdir
/mnt/fs/testdir:
TESTFILE.TXT
nsh>
o rmdir <dir-path>
Remove the specified <dir-path> directory from the mounted file system.
Recall that NuttX uses a pseudo file system for its root file system. The
rmdir command can only be used to remove directories from volumes set up
with the mount command; it cannot be used to remove directories from the
pseudo file system.
Example:
^^^^^^^^
nsh> mkdir /mnt/fs/tmp
nsh> ls -l /mnt/fs
/mnt/fs:
drw-rw-rw- 0 TESTDIR/
drw-rw-rw- 0 TMP/
nsh> rmdir /mnt/fs/tmp
nsh> ls -l /mnt/fs
ls -l /mnt/fs
/mnt/fs:
drw-rw-rw- 0 TESTDIR/
nsh>
o rmmod <module-name>
Remove the loadable OS module with the <module-name>. NOTE: An OS module
can only be removed if it is not busy.
Example:
nsh> lsmod
NAME INIT UNINIT ARG TEXT SIZE DATA SIZE
mydriver 20404659 20404625 0 20404580 552 204047a8 0
nsh> rmmod mydriver
nsh> lsmod
NAME INIT UNINIT ARG TEXT SIZE DATA SIZE
nsh>
o route ipv4|ipv6
Show the contents of routing table for IPv4 or IPv6.
If only IPv4 or IPv6 is enabled, then the argument is optional but, if provided,
must match the enabled internet protocol version.
o rptun start|stop <dev-path>
Start or stop the OpenAMP RPC tunnel device at <dev-path>.
o set [{+|-}{e|x|xe|ex}] [<name> <value>]
Set the variable <name> to the string <value> and or set NSH parser control
options.
For example, a variable may be set like this:
nsh> echo $foobar
nsh> set foobar foovalue
nsh> echo $foobar
foovalue
nsh>
If CONFIG_NSH_VARS is selected, the effect of this 'set' command is to set
the local NSH variable. Otherwise, the group-wide environment variable
will be set.
If the local NSH variable has already been 'promoted' to an environment
variable, then the 'set' command will set the value of the environment
variable rather than the local NSH variable.
NOTE: The Bash shell does not work this way. Bash would set the value of
both the local Bash variable and of the environment variable of the same
name to the same value.
If CONFIG_NSH_VARS is selected and no arguments are provided, then the
'set' command will list all list all NSH variables.
nsh> set
foolbar=foovalue
Set the 'exit on error control' and/or 'print a trace' of commands when parsing
scripts in NSH. The settinngs are in effect from the point of execution, until
they are changed again, or in the case of the init script, the settings are
returned to the default settings when it exits. Included child scripts will run
with the parents settings and changes made in the child script will effect the
parent on return.
Use 'set -e' to enable and 'set +e' to disable (ignore) the exit condition on commands.
The default is -e. Errors cause script to exit.
Use 'set -x' to enable and 'set +x' to disable (silence) printing a trace of the script
commands as they are ececuted.
The default is +x. No printing of a trace of script commands as they are executed.
Example 1 - no exit on command not found
set +e
notacommand
Example 2 - will exit on command not found
set -e
notacommand
Example 3 - will exit on command not found, and print a trace of the script commands
set -ex
Example 4 - will exit on command not found, and print a trace of the script commands
and set foobar to foovalue.
set -ex foobar foovalue
nsh> echo $foobar
foovalue
o sh <script-path>
Execute the sequence of NSH commands in the file referred
to by <script-path>.
o shutdown [--reboot]
Shutdown and power off the system or, optionally, reset and reboot the
system immediately. This command depends on hardware support to power
down or reset the system; one, both, or neither behavior may be
supported.
NOTE: The shutdown command duplicates the behavior of the poweroff and
reboot commands.
o sleep <sec>
Pause execution (sleep) of <sec> seconds.
o telnetd
The Telnet daemon may be started either programmatically by calling
nsh_telnetstart() or it may be started from the NSH command line using
this telnetd command.
Normally this command would be suppressed with CONFIG_NSH_DISABLE_TELNETD
because the Telnet daemon is automatically started in nsh_main.c. The
exception is when CONFIG_NETINIT_NETLOCAL is selected. IN that case, the
network is not enabled at initialization but rather must be enabled from
the NSH command line or via other applications.
In that case, calling nsh_telnetstart() before the the network is
initialized will fail.
o time "<command>"
Perform command timing. This command will execute the following <command>
string and then show how much time was required to execute the command.
Time is shown with a resolution of 100 microseconds which may be beyond
the resolution of many configurations. Note that the <command> must be
enclosed in quotation marks if it contains spaces or other
delimiters.
Example:
nsh> time "sleep 2"
2.0100 sec
nsh>
The additional 10 milliseconds in this example is due to the way that the
sleep command works: It always waits one system clock tick longer than
requested and this test setup used a 10 millisecond periodic system
timer. Sources of error could include various quantization errors,
competing CPU usage, and the additional overhead of the time command
execution itself which is included in the total.
The reported time is the elapsed time from starting of the command to
completion of the command. This elapsed time may not necessarily be
just the processing time for the command. It may included interrupt
level processing, for example. In a busy system, command processing could
be delayed if pre-empted by other, higher priority threads competing for
CPU time. So the reported time includes all CPU processing from the start
of the command to its finish possibly including unrelated processing time
during that interval.
Notice that:
nsh> time "sleep 2 &"
sleep [3:100]
0.0000 sec
nsh>
Since the sleep command is executed in background, the sleep command
completes almost immediately. As opposed to the following where the
time command is run in background with the sleep command:
nsh> time "sleep 2" &
time [3:100]
nsh>
2.0100 sec
o truncate -s <length> <file-path>
Shrink or extend the size of the regular file at <file-path> to the
specified <length>.
A <file-path> argument that does not exist is created. The <length>
option is NOT optional.
If a <file-path> is larger than the specified size, the extra data is
lost. If a <file-path> is shorter, it is extended and the extended part
reads as zero bytes.
o umount <dir-path>
Un-mount the file system at mount point <dir-path>. The umount command
can only be used to un-mount volumes previously mounted using mount
command.
Example:
nsh> ls /mnt/fs
/mnt/fs:
TESTDIR/
nsh> umount /mnt/fs
nsh> ls /mnt/fs
/mnt/fs:
nsh: ls: no such directory: /mnt/fs
nsh>
o unset <name>
Remove the value associated with the variable <name>. This will remove
the name-value pair from both the NSH local variables and the group-wide
environment variables. For example:
nsh> echo $foobar
foovalue
nsh> unset foobar
nsh> echo $foobar
nsh>
o urldecode [-f] <string or filepath>
o urlencode [-f] <string or filepath>
o uname [-a | -imnoprsv]
Print certain system information. With no options, the output is the same as -s.
-a Print all information, in the following order, except omit -p and -i if unknown:
-s, -o, Print the operating system name (NuttX)
-n Print the network node hostname (only available if CONFIG_NET=y)
-r Print the kernel release
-v Print the kernel version
-m Print the machine hardware name
-i Print the machine platform name
-p Print "unknown"
o useradd <username> <password>
Add a new user with <username> and <password>
o userdel <username>
Delete the user with the name <username>
o usleep <usec>
Pause execution (sleep) of <usec> microseconds.
o wget [-o <local-path>] <url>
Use HTTP to copy the file at <url> to the current directory.
Options:
-o <local-path>
The file will be saved relative to the current working directory
and with the same name as on the HTTP server unless <local-path>
is provided.
o xd <hex-address> <byte-count>
Dump <byte-count> bytes of data from address <hex-address>
Example:
^^^^^^^^
nsh> xd 410e0 512
Hex dump:
0000: 00 00 00 00 9c 9d 03 00 00 00 00 01 11 01 10 06 ................
0010: 12 01 11 01 25 08 13 0b 03 08 1b 08 00 00 02 24 ....%..........$
...
01f0: 08 3a 0b 3b 0b 49 13 00 00 04 13 01 01 13 03 08 .:.;.I..........
nsh>
Built-In Commands
^^^^^^^^^^^^^^^^^
In addition to the commands that are part of NSH listed above, there can be
additional, external "built-in" applications that can be added to NSH.
These are separately excecuble programs but will appear much like the
commands that are a part of NSH. The primary difference from the user's
perspective is that help information about the built-in applications is not
directly available from NSH. Rather, you will need to execute the
application with the -h option to get help about using the built-in
applications.
There are several built-in appliations in the apps/ repository. No attempt
is made here to enumerate all of them. But a few of the more common built-
in applications are listed below.
o ping [-c <count>] [-i <interval>] <ip-address>
ping6 [-c <count>] [-i <interval>] <ip-address>
Test the network communication with a remote peer. Example,
nsh> 10.0.0.1
PING 10.0.0.1 56 bytes of data
56 bytes from 10.0.0.1: icmp_seq=1 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=2 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=3 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=4 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=5 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=6 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=7 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=8 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=9 time=0 ms
56 bytes from 10.0.0.1: icmp_seq=10 time=0 ms
10 packets transmitted, 10 received, 0% packet loss, time 10190 ms
nsh>
ping6 differs from ping in that it uses IPv6 addressing.
NSH Configuration Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^
The availability of the above commands depends upon features that
may or may not be enabled in the NuttX configuration file. The
following table indicates the dependency of each command on NuttX
configuration settings. General configuration settings are discussed
in the NuttX Porting Guide. Configuration settings specific to NSH
as discussed at the bottom of this README file.
Command Dependencies on Configuration Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Command Depends on Configuration
---------- --------------------------
[ !CONFIG_NSH_DISABLESCRIPT
addroute CONFIG_NET && CONFIG_NET_ROUTE
arp CONFIG_NET && CONFIG_NET_ARP
base64dec CONFIG_NETUTILS_CODECS && CONFIG_CODECS_BASE64
base64enc CONFIG_NETUTILS_CODECS && CONFIG_CODECS_BASE64
basename --
break !CONFIG_NSH_DISABLESCRIPT && !CONFIG_NSH_DISABLE_LOOPS
cat --
cd !CONFIG_DISABLE_ENVIRON
cp --
dd --
delroute CONFIG_NET && CONFIG_NET_ROUTE
df !CONFIG_DISABLE_MOUNTPOINT
dirname --
dmesg CONFIG_RAMLOG_SYSLOG
echo --
env -- CONFIG_FS_PROCFS && !CONFIG_DISABLE_ENVIRON && !CONFIG_PROCFS_EXCLUDE_ENVIRON
exec --
exit --
export CONFIG_NSH_VARS && !CONFIG_DISABLE_ENVIRON
free --
get CONFIG_NET && CONFIG_NET_UDP && MTU >= 558 (see note 1)
help --
hexdump --
ifconfig CONFIG_NET && CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_NET
ifdown CONFIG_NET && CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_NET
ifup CONFIG_NET && CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_NET
insmod CONFIG_MODULE
irqinfo CONFIG_FS_PROCFS && CONFIG_SCHED_IRQMONITOR
kill --
losetup !CONFIG_DISABLE_MOUNTPOINT && CONFIG_DEV_LOOP
ln CONFIG_PSEUDOFS_SOFTLINK
ls --
lsmod CONFIG_MODULE && CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_MODULE
md5 CONFIG_NETUTILS_CODECS && CONFIG_CODECS_HASH_MD5
mb,mh,mw ---
mkdir !CONFIG_DISABLE_MOUNTPOINT || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS
mkfatfs !CONFIG_DISABLE_MOUNTPOINT && CONFIG_FSUTILS_MKFATFS
mkfifo CONFIG_PIPES && CONFIG_DEV_FIFO_SIZE > 0
mkrd !CONFIG_DISABLE_MOUNTPOINT
mount !CONFIG_DISABLE_MOUNTPOINT
mv !CONFIG_DISABLE_MOUNTPOINT || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS
nfsmount !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NET && CONFIG_NFS
nslookup CONFIG_LIBC_NETDB && CONFIG_NETDB_DNSCLIENT
password !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NSH_LOGIN_PASSWD
pmconfig CONFIG_PM && !CONFIG_NSH_DISABLE_PMCONFIG
poweroff CONFIG_BOARDCTL_POWEROFF
ps CONFIG_FS_PROCFS && !CONFIG_FS_PROCFS_EXCLUDE_PROC
put CONFIG_NET && CONFIG_NET_UDP && MTU >= 558 (see note 1,2)
pwd !CONFIG_DISABLE_ENVIRON
readlink CONFIG_PSEUDOFS_SOFTLINK
reboot CONFIG_BOARDCTL_RESET
rm !CONFIG_DISABLE_MOUNTPOINT || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS
rmdir !CONFIG_DISABLE_MOUNTPOINT || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS
rmmod CONFIG_MODULE
route CONFIG_FS_PROCFS && CONFIG_FS_PROCFS_EXCLUDE_NET &&
!CONFIG_FS_PROCFS_EXCLUDE_ROUTE && CONFIG_NET_ROUTE &&
!CONFIG_NSH_DISABLE_ROUTE && (CONFIG_NET_IPv4 || CONFIG_NET_IPv6)
rptun CONFIG_RPTUN
set CONFIG_NSH_VARS || !CONFIG_DISABLE_ENVIRON
sh CONFIG_NFILE_STREAMS > 0 && !CONFIG_NSH_DISABLESCRIPT
shutdown CONFIG_BOARDCTL_POWEROFF || CONFIG_BOARDCTL_RESET
sleep --
test !CONFIG_NSH_DISABLESCRIPT
telnetd CONFIG_NSH_TELNET && !CONFIG_NSH_DISABLE_TELNETD
time ---
truncate !CONFIG_DISABLE_MOUNTPOINT
umount !CONFIG_DISABLE_MOUNTPOINT
uname !CONFIG_NSH_DISABLE_UNAME
unset CONFIG_NSH_VARS || !CONFIG_DISABLE_ENVIRON
urldecode CONFIG_NETUTILS_CODECS && CONFIG_CODECS_URLCODE
urlencode CONFIG_NETUTILS_CODECS && CONFIG_CODECS_URLCODE
useradd !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NSH_LOGIN_PASSWD
userdel !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NSH_LOGIN_PASSWD
usleep --
get CONFIG_NET && CONFIG_NET_TCP
xd ---
* NOTES:
1. Because of hardware padding, the actual MTU required for put and get
operations size may be larger.
2. Special TFTP server start-up options will probably be required to permit
creation of file for the correct operation of the put command.
In addition, each NSH command can be individually disabled via one of the following
settings. All of these settings make the configuration of NSH potentially complex but
also allow it to squeeze into very small memory footprints.
CONFIG_NSH_DISABLE_ADDROUTE, CONFIG_NSH_DISABLE_BASE64DEC, CONFIG_NSH_DISABLE_BASE64ENC,
CONFIG_NSH_DISABLE_BASENAME, CONFIG_NSH_DISABLE_CAT, CONFIG_NSH_DISABLE_CD,
CONFIG_NSH_DISABLE_CP, CONFIG_NSH_DISABLE_DD, CONFIG_NSH_DISABLE_DELROUTE,
CONFIG_NSH_DISABLE_DF, CONFIG_NSH_DISABLE_DIRNAME, CONFIG_NSH_DISABLE_DMESG,
CONFIG_NSH_DISABLE_ECHO, CONFIG_NSH_DISABLE_ENV, CONFIG_NSH_DISABLE_EXEC,
CONFIG_NSH_DISABLE_EXIT, CONFIG_NSH_DISABLE_EXPORT, CONFIG_NSH_DISABLE_FREE,
CONFIG_NSH_DISABLE_GET, CONFIG_NSH_DISABLE_HELP, CONFIG_NSH_DISABLE_HEXDUMP,
CONFIG_NSH_DISABLE_IFCONFIG, CONFIG_NSH_DISABLE_IFUPDOWN, CONFIG_NSH_DISABLE_KILL,
CONFIG_NSH_DISABLE_LOSETUP, CONFIG_NSH_DISABLE_LN, CONFIG_NSH_DISABLE_LS,
CONFIG_NSH_DISABLE_MD5, CONFIG_NSH_DISABLE_MB, CONFIG_NSH_DISABLE_MKDIR,
CONFIG_NSH_DISABLE_MKFATFS, CONFIG_NSH_DISABLE_MKFIFO, CONFIG_NSH_DISABLE_MKRD,
CONFIG_NSH_DISABLE_MH, CONFIG_NSH_DISABLE_MODCMDS, CONFIG_NSH_DISABLE_MOUNT,
CONFIG_NSH_DISABLE_MW, CONFIG_NSH_DISABLE_MV, CONFIG_NSH_DISABLE_NFSMOUNT,
CONFIG_NSH_DISABLE_NSLOOKUP, CONFIG_NSH_DISABLE_PASSWD, CONFIG_NSH_DISABLE_PING6,
CONFIG_NSH_DISABLE_POWEROFF, CONFIG_NSH_DISABLE_PS, CONFIG_NSH_DISABLE_PUT,
CONFIG_NSH_DISABLE_PWD, CONFIG_NSH_DISABLE_READLINK, CONFIG_NSH_DISABLE_REBOOT,
CONFIG_NSH_DISABLE_RM, CONFIG_NSH_DISABLE_RPTUN, CONFIG_NSH_DISABLE_RMDIR,
CONFIG_NSH_DISABLE_ROUTE, CONFIG_NSH_DISABLE_SET, CONFIG_NSH_DISABLE_SH,
CONFIG_NSH_DISABLE_SHUTDOWN, CONFIG_NSH_DISABLE_SLEEP, CONFIG_NSH_DISABLE_TEST,
CONFIG_NSH_DIABLE_TIME, CONFIG_NSH_DISABLE_TRUNCATE, CONFIG_NSH_DISABLE_UMOUNT,
CONFIG_NSH_DISABLE_UNSET, CONFIG_NSH_DISABLE_URLDECODE, CONFIG_NSH_DISABLE_URLENCODE,
CONFIG_NSH_DISABLE_USERADD, CONFIG_NSH_DISABLE_USERDEL, CONFIG_NSH_DISABLE_USLEEP,
CONFIG_NSH_DISABLE_WGET, CONFIG_NSH_DISABLE_XD
Verbose help output can be suppressed by defining CONFIG_NSH_HELP_TERSE. In that
case, the help command is still available but will be slightly smaller.
Built-in Application Configuration Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
All built-in applications require that support for NSH built-in applications has been enabled. This support is enabled with CONFIG_BUILTIN=y and CONFIG_NSH_BUILTIN_APPS=y.
Application Depends on Configuration
----------- --------------------------
ping CONFIG_NET && CONFIG_NET_ICMP && CONFIG_NET_ICMP_SOCKET &&
CONFIG_SYSTEM_PING
ping6 CONFIG_NET && CONFIG_NET_ICMPv6 && CONFIG_NET_ICMPv6_SOCKET &&
CONFIG_SYSTEM_PING6
NSH-Specific Configuration Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The behavior of NSH can be modified with the following settings in
the boards/<arch>/<chip>/<board>/configs/<config>/defconfig file:
* CONFIG_NSH_READLINE
Selects the minimal implementation of readline(). This minimal
implementation provides on backspace for command line editing.
* CONFIG_NSH_CLE
Selects the more extensive, EMACS-like command line editor.
Select this option only if (1) you don't mind a modest increase
in the FLASH footprint, and (2) you work with a terminal that
support VT100 editing commands.
Selecting this option will add probably 1.5-2KB to the FLASH
footprint.
* CONFIG_NSH_BUILTIN_APPS
Support external registered, "builtin" applications that can be
executed from the NSH command line (see apps/README.txt for
more information).
* CONFIG_NSH_FILEIOSIZE
Size of a static I/O buffer used for file access (ignored if
there is no file system). Default is 1024.
* CONFIG_NSH_STRERROR
strerror(errno) makes more readable output but strerror() is
very large and will not be used unless this setting is 'y'.
This setting depends upon the strerror() having been enabled
with CONFIG_LIBC_STRERROR.
* CONFIG_NSH_LINELEN
The maximum length of one command line and of one output line.
Default: 80
* CONFIG_NSH_DISABLE_SEMICOLON
By default, you can enter multiple NSH commands on a line with
each command separated by a semicolon. You can disable this
feature to save a little memory on FLASH challenged platforms.
Default: n
* CONFIG_NSH_CMDPARMS
If selected, then the output from commands, from file applications, and
from NSH built-in commands can be used as arguments to other
commands. The entity to be executed is identified by enclosing the
command line in back quotes. For example,
set FOO `myprogram $BAR`
Will execute the program named myprogram passing it the value of the
environment variable BAR. The value of the environment variable FOO
is then set output of myprogram on stdout. Because this feature commits
significant resources, it is disabled by default.
The CONFIG_NSH_CMDPARMS interim output will be retained in a temporary
file. Full path to a directory where temporary files can be created is
taken from CONFIG_LIBC_TMPDIR and it defaults to /tmp if
CONFIG_LIBC_TMPDIR is not set.
* CONFIG_NSH_MAXARGUMENTS
The maximum number of NSH command arguments. Default: 6
* CONFIG_NSH_ARGCAT
Support concatenation of strings with environment variables or command
output. For example:
set FOO XYZ
set BAR 123
set FOOBAR ABC_${FOO}_${BAR}
would set the environment variable FOO to XYZ, BAR to 123 and FOOBAR
to ABC_XYZ_123. If NSH_ARGCAT is not selected, then a slightly small
FLASH footprint results but then also only simple environment
variables like $FOO can be used on the command line.
* CONFIG_NSH_VARS
By default, there are no internal NSH variables. NSH will use OS
environment variables for all variable storage. If this option, NSH
will also support local NSH variables. These variables are, for the
most part, transparent and work just like the OS environment
variables. The difference is that when you create new tasks, all of
environment variables are inherited by the created tasks. NSH local
variables are not.
If this option is enabled (and CONFIG_DISABLE_ENVIRON is not), then a
new command called 'export' is enabled. The export command works very
must like the set command except that is operates on environment
variables. When CONFIG_NSH_VARS is enabled, there are changes in the
behavior of certain commands
============== =========================== ===========================
CMD w/o CONFIG_NSH_VARS w/CONFIG_NSH_VARS
============== =========================== ===========================
set <a> <b> Set environment var a to b Set NSH var a to b
set Causes an error Lists all NSH variables
unset <a> Unsets environment var a Unsets both environment var
and NSH var a
export <a> <b> Causes an error Unsets NSH var a. Sets
environment var a to b.
export <a> Causes an error Sets environment var a to
NSH var b (or ""). Unsets
local var a.
env Lists all environment Lists all environment
variables variables (only)
============== =========================== ===========================
* CONFIG_NSH_QUOTE
Enables back-slash quoting of certain characters within the command.
This option is useful for the case where an NSH script is used to
dynamically generate a new NSH script. In that case, commands must
be treated as simple text strings without interpretation of any
special characters. Special characters such as $, `, ", and others
must be retained intact as part of the test string. This option is
currently only available is CONFIG_NSH_ARGCAT is also selected.
* CONFIG_NSH_NESTDEPTH
The maximum number of nested if-then[-else]-fi sequences that
are permissible. Default: 3
* CONFIG_NSH_DISABLESCRIPT
This can be set to 'y' to suppress support for scripting. This
setting disables the 'sh', 'test', and '[' commands and the
if-then[-else]-fi construct. This would only be set on systems
where a minimal footprint is a necessity and scripting is not.
* CONFIG_NSH_DISABLE_ITEF
If scripting is enabled, then then this option can be selected to
suppress support for if-then-else-fi sequences in scripts. This would
only be set on systems where some minimal scripting is required but
if-then-else-fi is not.
* CONFIG_NSH_DISABLE_LOOPS
If scripting is enabled, then then this option can be selected
suppress support for while-do-done and until-do-done sequences in
scripts. This would only be set on systems where some minimal
scripting is required but looping is not.
* CONFIG_NSH_DISABLEBG
This can be set to 'y' to suppress support for background
commands. This setting disables the 'nice' command prefix and
the '&' command suffix. This would only be set on systems
where a minimal footprint is a necessity and background command
execution is not.
* CONFIG_NSH_MMCSDMINOR
If the architecture supports an MMC/SD slot and if the NSH
architecture specific logic is present, this option will provide
the MMC/SD minor number, i.e., the MMC/SD block driver will
be registered as /dev/mmcsdN where N is the minor number.
Default is zero.
* CONFIG_NSH_ROMFSETC
Mount a ROMFS file system at /etc and provide a startup script
at /etc/init.d/rcS. The default startup script will mount
a FAT FS RAMDISK at /tmp but the logic is easily extensible.
* CONFIG_NSH_CONSOLE
If CONFIG_NSH_CONSOLE is set to 'y', then a serial
console front-end is selected.
Normally, the serial console device is a UART and RS-232
interface. However, if CONFIG_USBDEV is defined, then a USB
serial device may, instead, be used if the one of
the following are defined:
CONFIG_PL2303 and CONFIG_PL2303_CONSOLE - Sets up the
Prolifics PL2303 emulation as a console device
at /dev/console.
CONFIG_CDCACM and CONFIG_CDCACM_CONSOLE - Sets up the
CDC/ACM serial device as a console device at
dev/console.
CONFIG_NSH_USBCONSOLE
If defined, then the an arbitrary USB device may be used
to as the NSH console. In this case, CONFIG_NSH_USBCONDEV
must be defined to indicate which USB device to use as
the console.
CONFIG_NSH_USBCONDEV
If CONFIG_NSH_USBCONSOLE is set to 'y', then CONFIG_NSH_USBCONDEV
must also be set to select the USB device used to support
the NSH console. This should be set to the quoted name of a
read-/write-able USB driver. Default: "/dev/ttyACM0".
If there are more than one USB devices, then a USB device
minor number may also need to be provided:
CONFIG_NSH_USBDEV_MINOR
The minor device number of the USB device. Default: 0
CONFIG_NSH_USBKBD
Normally NSH uses the same device for stdin, stdout, and stderr. By
default, that device is /dev/console. If this option is selected,
then NSH will use a USB HID keyboard for stdin. In this case, the
keyboard is connected directly to the target (via a USB host
interface) and the data from the keyboard will drive NSH. NSH
output (stdout and stderr) will still go to /dev/console.
CONFIG_NSH_USBKBD_DEVNAME
If NSH_USBKBD is set to 'y', then NSH_USBKBD_DEVNAME must also be
set to select the USB keyboard device used to support the NSH
console input. This should be set to the quoted name of a read-
able keyboard driver. Default: "/dev/kbda".
CONFIG_NSH_USBDEV_TRACE
If USB tracing is enabled (CONFIG_USBDEV_TRACE), then NSH can
be configured to show the buffered USB trace data after each
NSH command:
If CONFIG_NSH_USBDEV_TRACE is selected, then USB trace data
can be filtered as follows. Default: Only USB errors are traced.
CONFIG_NSH_USBDEV_TRACEINIT
Show initialization events
CONFIG_NSH_USBDEV_TRACECLASS
Show class driver events
CONFIG_NSH_USBDEV_TRACETRANSFERS
Show data transfer events
CONFIG_NSH_USBDEV_TRACECONTROLLER
Show controller events
CONFIG_NSH_USBDEV_TRACEINTERRUPTS
Show interrupt-related events.
* CONFIG_NSH_ALTCONDEV and CONFIG_NSH_CONDEV
If CONFIG_NSH_CONSOLE is set to 'y', then CONFIG_NSH_ALTCONDEV may also
be selected to enable use of an alternate character device to support
the NSH console. If CONFIG_NSH_ALTCONDEV is selected, then
CONFIG_NSH_CONDEV holds the quoted name of a readable/write-able
character driver such as: CONFIG_NSH_CONDEV="/dev/ttyS1". This is
useful, for example, to separate the NSH command line from the system
console when the system console is used to provide debug output.
Default: stdin and stdout (probably "/dev/console")
NOTE 1: When any other device other than /dev/console is used for a
user interface, (1) linefeeds (\n) will not be expanded to carriage
return / linefeeds (\r\n). You will need to configure your terminal
program to account for this. And (2) input is not automatically
echoed so you will have to turn local echo on.
NOTE 2: This option forces the console of all sessions to use
NSH_CONDEV. Hence, this option only makes sense for a system that
supports only a single session. This option is, in particular,
incompatible with Telnet sessions because each Telnet session must
use a different console device.
* CONFIG_NSH_TELNET
If CONFIG_NSH_TELNET is set to 'y', then a TELENET
server front-end is selected. When this option is provided,
you may log into NuttX remotely using telnet in order to
access NSH.
* CONFIG_NSH_ARCHINIT
Set if your board provides architecture specific initialization
via the board-interface function boardctl(). This function will
be called early in NSH initialization to allow board logic to
do such things as configure MMC/SD slots.
If Telnet is selected for the NSH console, then we must configure
the resources used by the Telnet daemon and by the Telnet clients.
* CONFIG_NSH_TELNETD_PORT - The telnet daemon will listen on this
TCP port number for connections. Default: 23
* CONFIG_NSH_TELNETD_DAEMONPRIO - Priority of the Telnet daemon.
Default: SCHED_PRIORITY_DEFAULT
* CONFIG_NSH_TELNETD_DAEMONSTACKSIZE - Stack size allocated for the
Telnet daemon. Default: 2048
* CONFIG_NSH_TELNETD_CLIENTPRIO- Priority of the Telnet client.
Default: SCHED_PRIORITY_DEFAULT
* CONFIG_NSH_TELNETD_CLIENTSTACKSIZE - Stack size allocated for the
Telnet client. Default: 2048
One or both of CONFIG_NSH_CONSOLE and CONFIG_NSH_TELNET
must be defined. If CONFIG_NSH_TELNET is selected, then there some
other configuration settings that apply:
* CONFIG_NET=y
Of course, networking must be enabled
* CONFIG_NET_TCP=y
TCP/IP support is required for telnet (as well as various other TCP-related
configuration settings).
* CONFIG_NSH_IOBUFFER_SIZE
Determines the size of the I/O buffer to use for sending/
receiving TELNET commands/responses
* CONFIG_NETINIT_DHCPC
Obtain the IP address via DHCP.
* CONFIG_NETINIT_IPADDR
If CONFIG_NETINIT_DHCPC is NOT set, then the static IP
address must be provided.
* CONFIG_NETINIT_DRIPADDR
Default router IP address
* CONFIG_NETINIT_NETMASK
Network mask
* CONFIG_NETINIT_NOMAC
Set if your ethernet hardware has no built-in MAC address.
If set, a bogus MAC will be assigned.
If you use DHCPC, then some special configuration network options are
required. These include:
* CONFIG_NET=y
Of course, networking must be enabled
* CONFIG_NET_UDP=y
UDP support is required for DHCP (as well as various other UDP-related
configuration settings)
* CONFIG_NET_BROADCAST=y
UDP broadcast support is needed.
* CONFIG_NET_ETH_PKTSIZE=650 (or larger)
Per RFC2131 (p. 9), the DHCP client must be prepared to receive DHCP
messages of up to 576 bytes (excluding Ethernet, IP, or UDP headers and FCS).
NOTE: Note that the actual MTU setting will depend upon the specific
link protocol. Here Ethernet is indicated.
If CONFIG_NSH_ROMFSETC is selected, then the following additional
configuration setting apply:
* CONFIG_NSH_ROMFSMOUNTPT
The default mountpoint for the ROMFS volume is /etc, but that
can be changed with this setting. This must be a absolute path
beginning with '/'.
* CONFIG_NSH_INITSCRIPT
This is the relative path to the startup script within the mountpoint.
The default is init.d/rcS. This is a relative path and must not
start with '/'.
* CONFIG_NSH_ROMFSDEVNO
This is the minor number of the ROMFS block device. The default is
'0' corresponding to /dev/ram0.
* CONFIG_NSH_ROMFSSECTSIZE
This is the sector size to use with the ROMFS volume. Since the
default volume is very small, this defaults to 64 but should be
increased if the ROMFS volume were to be become large. Any value
selected must be a power of 2.
When the default rcS file used when CONFIG_NSH_ROMFSETC is
selected, it will mount a FAT FS under /tmp. The following selections
describe that FAT FS.
* CONFIG_NSH_FATDEVNO
This is the minor number of the FAT FS block device. The default is
'1' corresponding to /dev/ram1.
* CONFIG_NSH_FATSECTSIZE
This is the sector size use with the FAT FS. Default is 512.
* CONFIG_NSH_FATNSECTORS
This is the number of sectors to use with the FAT FS. Default is
1024. The amount of memory used by the FAT FS will be
CONFIG_NSH_FATSECTSIZE * CONFIG_NSH_FATNSECTORS
bytes.
* CONFIG_NSH_FATMOUNTPT
This is the location where the FAT FS will be mounted. Default
is /tmp.
Common Problems
^^^^^^^^^^^^^^^
Problem:
The function 'readline' is undefined.
Usual Cause:
The following is missing from your defconfig file:
CONFIG_SYSTEM_READLINE=y
4adb83c754