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
- NSH Configuration Settings
Command Dependencies on 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.
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 configs/<board>/include will be
used. NOTE when the OS is configured, include/arch/board will
be linked to configs/<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 $?. This command
is used most frequently as the conditional command following the
'if' in the if-then[-else]-fi construct.
Expression Syntax:
------------------
expression = simple-expression | !expression |
expression -o expression | expression -a expression
simple-expression = unary-expression | binary-expression
unary-expression = string-unary | file-unary
string-unary = -n string | -z string
file-unary = -b file | -c file | -d file | -e file | -f file |
-r file | -s file | -w file
binary-expression = string-binary | numeric-binary
string-binary = string = string | string == string | string != string
numeric-binary = integer -eq integer | integer -ge integer |
integer -gt integer | integer -le integer |
integer -lt integer | integer -ne integer
o addroute <target> <netmask> <router>
This command adds an entry in the routing table. The new entry
will map the IP address of a router on a local network(<router>)
to an external network characterized by the <target> IP address and
a network mask <netmask>
Example:
nsh> addroute 1.1.1.1 2.2.2.2 3.3.3.3
o base64dec [-w] [-f] <string or filepath>
o base64dec [-w] [-f] <string or filepath>
o break
The break command is only meaningful within the body of the a while or
until loop, between the do and done tokens. Outside of a loop, break
command does nothing. If the break command is executed within the body
of a loop, the loop will immediately terminate and execution will
continue with the next command immediately following the done token.
o cat <path> [<path> [<path> ...]]
This command copies and concatenates all of the files at <path>
to the console (or to another file if the output is redirected).
o cd [<dir-path>|-|~|..]
Changes the current working directory (PWD). Also sets the
previous working directory environment variable (OLDPWD).
FORMS:
------
'cd <dir-path>' sets the current working directory to <dir-path>.
'cd -' sets the current working directory to the previous
working directory ($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. This command is only supported
if the platform supported RTC hardware (CONFIG_RTC=y).
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 devic, 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>
Example:
nsh> delroute 1.1.1.1 2.2.2.2
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 echo [<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).
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 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.
o ifdown <nic-name>
Take down the interface identified by the name <nic-name>.
Example:
ifdown eth0
o ifup <nic-name>
Bring up down the interface identified by the name <nic-name>.
Example:
ifup eth0
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 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 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>] <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.
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<n> (if <n> 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> <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 ps
Show the currently active threads and tasks. For example,
nsh> ps
PID PRI SCHD TYPE NP STATE NAME
0 0 FIFO TASK READY Idle Task()
1 128 RR TASK RUNNING init()
2 128 FIFO TASK WAITSEM nsh_telnetmain()
3 100 RR PTHREAD WAITSEM <pthread>(21)
nsh>
o ping [-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>
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 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 set <name> <value>
Set the environment variable <name> to the sting <value>.
For example,
nsh> echo $foobar
nsh> set foobar foovalue
nsh> echo $foobar
foovalue
nsh>
o sh <script-path>
Execute the sequence of NSH commands in the file referred
to by <script-path>.
o sleep <sec>
Pause execution (sleep) of <sec> seconds.
o unset <name>
Remove the value associated with the environment variable
<name>. Example:
nsh> echo $foobar
foovalue
nsh> unset foobar
nsh> echo $foobar
nsh>
o urldecode [-f] <string or filepath>
o urlencode [-f] <string or filepath>
o usleep <usec>
Pause execution (sleep) of <usec> microseconds.
o wget [-o <local-path>] <url>
Use HTTP to copy the file at <url> to the current directory.
Options:
-o <local-path>
The file will be saved relative to the current working directory
and with the same name as on the HTTP server unless <local-path>
is provided.
o xd <hex-address> <byte-count>
Dump <byte-count> bytes of data from address <hex-address>
Example:
^^^^^^^^
nsh> xd 410e0 512
Hex dump:
0000: 00 00 00 00 9c 9d 03 00 00 00 00 01 11 01 10 06 ................
0010: 12 01 11 01 25 08 13 0b 03 08 1b 08 00 00 02 24 ....%..........$
...
01f0: 08 3a 0b 3b 0b 49 13 00 00 04 13 01 01 13 03 08 .:.;.I..........
nsh>
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
base64dec CONFIG_NETUTILS_CODECS && CONFIG_CODECS_BASE64
base64enc CONFIG_NETUTILS_CODECS && CONFIG_CODECS_BASE64
break !CONFIG_NSH_DISABLESCRIPT && !CONFIG_NSH_DISABLE_LOOPS
cat CONFIG_NFILE_DESCRIPTORS > 0
cd !CONFIG_DISABLE_ENVIRON && CONFIG_NFILE_DESCRIPTORS > 0
cp CONFIG_NFILE_DESCRIPTORS > 0
dd CONFIG_NFILE_DESCRIPTORS > 0
delrout CONFIG_NET && CONFIG_NET_ROUTE
df !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_READABLE (see note 3)
echo --
exec --
exit --
free --
get CONFIG_NET && CONFIG_NET_UDP && CONFIG_NFILE_DESCRIPTORS > 0 && MTU >= 558 (see note 1)
help --
hexdump CONFIG_NFILE_DESCRIPTORS > 0
ifconfig CONFIG_NET
ifdown CONFIG_NET
ifup CONFIG_NET
kill !CONFIG_DISABLE_SIGNALS
losetup !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0
ls CONFIG_NFILE_DESCRIPTORS > 0
md5 CONFIG_NETUTILS_CODECS && CONFIG_CODECS_HASH_MD5
mb,mh,mw ---
mkdir (((!CONFIG_DISABLE_MOUNTPOINT && CONFIG_FS_WRITABLE) || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS) && CONFIG_NFILE_DESCRIPTORS > 0)
mkfatfs !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_FAT
mkfifo CONFIG_NFILE_DESCRIPTORS > 0
mkrd !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_WRITABLE (see note 4)
mount !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_READABLE (see note 3)
mv (((!CONFIG_DISABLE_MOUNTPOINT && CONFIG_FS_WRITABLE) || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS) && CONFIG_NFILE_DESCRIPTORS > 0) (see note 4)
nfsmount !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NET && CONFIG_NFS
ping CONFIG_NET && CONFIG_NET_ICMP && CONFIG_NET_ICMP_PING && !CONFIG_DISABLE_SIGNALS
ps --
put CONFIG_NET && CONFIG_NET_UDP && CONFIG_NFILE_DESCRIPTORS > 0 && MTU >= 558 (see note 1,2)
pwd !CONFIG_DISABLE_ENVIRON && CONFIG_NFILE_DESCRIPTORS > 0
rm (((!CONFIG_DISABLE_MOUNTPOINT && CONFIG_FS_WRITABLE) || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS) && CONFIG_NFILE_DESCRIPTORS > 0)
rmdir (((!CONFIG_DISABLE_MOUNTPOINT && CONFIG_FS_WRITABLE) || !CONFIG_DISABLE_PSEUDOFS_OPERATIONS) && CONFIG_NFILE_DESCRIPTORS > 0)
set !CONFIG_DISABLE_ENVIRON
sh CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NFILE_STREAMS > 0 && !CONFIG_NSH_DISABLESCRIPT
sleep !CONFIG_DISABLE_SIGNALS
test !CONFIG_NSH_DISABLESCRIPT
umount !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_READABLE
unset !CONFIG_DISABLE_ENVIRON
urldecode CONFIG_NETUTILS_CODECS && CONFIG_CODECS_URLCODE
urlencode CONFIG_NETUTILS_CODECS && CONFIG_CODECS_URLCODE
usleep !CONFIG_DISABLE_SIGNALS
get CONFIG_NET && CONFIG_NET_TCP && CONFIG_NFILE_DESCRIPTORS > 0
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.
3. CONFIG_FS_READABLE is not a user configuration but is set automatically
if any readable file system is selected. At present, this is either CONFIG_FS_FAT
and CONFIG_FS_ROMFS.
4. CONFIG_FS_WRITABLE is not a user configuration but is set automatically
if any writeable file system is selected. At present, this is only CONFIG_FS_FAT.
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_CAT, CONFIG_NSH_DISABLE_CD, CONFIG_NSH_DISABLE_CP,
CONFIG_NSH_DISABLE_DD, CONFIG_NSH_DISABLE_DELROUTE, CONFIG_NSH_DISABLE_DF,
CONFIG_NSH_DISABLE_ECHO, CONFIG_NSH_DISABLE_EXEC, CONFIG_NSH_DISABLE_EXIT,
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_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_MOUNT, CONFIG_NSH_DISABLE_MW,
CONFIG_NSH_DISABLE_MV, CONFIG_NSH_DISABLE_NFSMOUNT, CONFIG_NSH_DISABLE_PS,
CONFIG_NSH_DISABLE_PING, CONFIG_NSH_DISABLE_PUT, CONFIG_NSH_DISABLE_PWD,
CONFIG_NSH_DISABLE_RM, CONFIG_NSH_DISABLE_RMDIR, CONFIG_NSH_DISABLE_SET,
CONFIG_NSH_DISABLE_SH, CONFIG_NSH_DISABLE_SLEEP, CONFIG_NSH_DISABLE_TEST,
CONFIG_NSH_DISABLE_UMOUNT, CONFIG_NSH_DISABLE_UNSET, CONFIG_NSH_DISABLE_URLDECODE,
CONFIG_NSH_DISABLE_URLENCODE, 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.
NSH-Specific Configuration Settings
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The behavior of NSH can be modified with the following settings in
the configs/<board-name>/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 $BAR`
Will execute the program named myprogram passing it the value of the
environment variable BAR. The value of the environment variable FOO
is then set output of myprogram on stdout. Because this feature commits
significant resources, it is disabled by default.
* CONFIG_NSH_TMPDIR
If CONFIG_NSH_CMDPARMS is selected, then function output will be retained
in a temporary file. In that case, this string must be provided to
specify the full path to a directory where temporary files can be
created. This would be a good application of RAM disk: To provide
temporary storage for function output.
* CONFIG_NSH_MAXARGUMENTS
The maximum number of NSH command arguments. Default: 6
* CONFIG_NSH_ARGCAT
Support concatenation of strings with environment variables or command
output. For example:
set FOO XYZ
set BAR 123
set FOOBAR ABC_${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_NESTDEPTH
The maximum number of nested if-then[-else]-fi sequences that
are permissable. 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 afer 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-specific function nsh_archinitialize(). 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_NSOCKET_DESCRIPTORS
And, of course, you must allocate some socket descriptors.
* 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/reponses
* CONFIG_NSH_DHCPC
Obtain the IP address via DHCP.
* CONFIG_NSH_IPADDR
If CONFIG_NSH_DHCPC is NOT set, then the static IP
address must be provided.
* CONFIG_NSH_DRIPADDR
Default router IP address
* CONFIG_NSH_NETMASK
Network mask
* CONFIG_NSH_NOMAC
Set if your ethernet hardware has no built-in MAC address.
If set, a bogus MAC will be assigned.
* CONFIG_NSH_MAX_ROUNDTRIP
This is the maximum round trip for a response to a ICMP ECHO request.
It is in units of deciseconds. The default is 20 (2 seconds).
If you use DHCPC, then some special configuration network options are
required. These include:
* CONFIG_NET=y
Of course, networking must be enabled
* CONFIG_NSOCKET_DESCRIPTORS
And, of course, you must allocate some socket descriptors.
* 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_MTU=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. Defalt 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:
Using NSH over serial, the "nsh>" prompt repeats over and over again
with no serial input.
Usual Cause:
NSH over serial needs to use the interrupt driven serial driver
(drivers/serial/serial.c) not the polled serial driver (drivers/serial/lowconsole.c).
Make sure that the polled console is disabled in the OS configuration
file, .config. That file should have CONFIG_DEV_LOWCONSOLE=n for
NSH over serial.
Problem:
The function 'readline' is undefined.
Usual Cause:
The following is missing from your defconfig file:
CONFIG_SYSTEM_READLINE=y
