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 - 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: Command with re-directed output: > >> Background command: & Re-directed background command: > & >> & Where: is any one of the simple commands listed later. is the full or relative path to any writable object in the filesystem 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 >]] [> |>> ] [&] Where is any value between -20 and 19 where lower (more negative values) correspond to higher priorities. The default niceness is 10. 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 commnd). The syntax is as follows: if then [sequence of ] else [sequence of ] fi 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 filesystem containing the following: |--init.d/ `-- rcS Where rcS is the NSH start-up script - NSH will then mount the ROMFS filesystem 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 XXXRDMOUNTPOUNTXXX 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//include will be used. NOTE when the OS is configured, include/arch/board will be linked to configs//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 containg the ROMFS file system image. Simple Commands ^^^^^^^^^^^^^^^ o [ ] o test These are two alternative forms of the same command. They support evaluation of a boolean expression which sets $?. This command is used most frequently as the conditional command following the 'if' in the if-then[-else]-fi construct. Expression Syntax: ------------------ expression = simple-expression | !expression | expression -o expression | expression -a expression simple-expression = unary-expression | binary-expression unary-expression = string-unary | file-unary string-unary = -n string | -z string file-unary = -b file | -c file | -d file | -e file | -f file | -r file | -s file | -w file binary-expression = string-binary | numeric-binary string-binary = string = string | string == string | string != string numeric-binary = integer -eq integer | integer -ge integer | integer -gt integer | integer -le integer | integer -lt integer | integer -ne integer o cat [ [ ...]] This command copies and concatentates all of the files at to the console (or to another file if the output is redirected). o cd [|-|~|..] Changes the current working directory (PWD). Also sets the previous working directory environment variable (OLDPWD). FORMS: ------ 'cd ' sets the current working directory to . 'cd -' sets the current working directory to the previous working directory ($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 cp

Copy of the contents of the file at to the location in the filesystem indicated by o dd if= of= [bs=] [count=] [skip=] Copy blocks from to . or 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 echo [ [...]] Copy the sequence of strings and expanded environment variables to console out (or to a file if the output is re-directed). o exec Execute the user logic at address . NSH will pause until the execution unless the user logic is executed in background via 'exec &' 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 ] -h

Use TFTP to copy the file at from the host whose IP address is identified by . Other options: -f The file will be saved relative to the current working directory unless is provided. -b|-n Selects either binary ("octect") or test ("netascii") transfer mode. Default: text. o help Presents summary information about each command to console. o ifconfig 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 uIP statistics are enabled (CONFIG_NET_STATISTICS), then this command will also show the detailed state of uIP. o kill - Send the to the task identified by . o losetup [-d ] | [[-o ] [-r]

] Setup or teardown the loop device: 1. Teardown the setup for the loop device at : losetup d 2. Setup the loop device at to access the file at as a block device: losetup [-o ] [-r]

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] Show the contents of the directory at . NOTE: must refer to a directory and no other filesystem 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 mb [=][ ] o mh [=][ ] o mw [=][ ] Access memory using byte size access (mb), 16-bit accesses (mh), or 32-bit access (mw). In each case, . Specifies the address to be accessed. The current value at that address will always be read and displayed. =. Read the value, then write to the location. . Perform the mb, mh, or mw operation on a total of bytes, increment the 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 Create the directory at . All components of of except the final directory name must exist on a mounted file system; the final directory must not. Recall that NuttX uses a pseudo filesystem 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 filesystem. 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 Format a fat file system on the block device specified by path. NSH provides this command to access the mkfatfs() NuttX API. This block device must reside in the NuttX psuedo filesystem and must have been created by some call to register_blockdriver() (see include/nuttx/fs.h). o mkfifo Creates a FIFO character device anywhere in the pseudo file system, creating whatever psuedo 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 ] [-s ] Create a ramdisk consisting of , each of size (or 512 bytes if is not specified. The ramdisk will be registered as /dev/ram (if 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

The 'mount' command mounts a file system in the NuttX psuedo filesystem. 'mount' performs a three way associating, binding File system. The '-t ' option identifies the type of file system that has been formatted on the . As of this writing, vfat is the only supported value for Block Device. The argument is the full or relative path to a block driver inode in the psuedo filesystem. By convention, this is a name under the /dev sub-directory. This must have been previously formatted with the same file system type as specified by Mount Point. The mount point is the location in the psuedo file system where the mounted volume will appear. This mount point can only reside in the NuttX psuedo filesystem. By convention, this mount point is a subdirectory under /mnt. The mount command will create whatever psuedo 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 psuedo file system, it may be access in the same way as other objects in the file system. Example: ^^^^^^^^ 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> 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 (21) nsh> o ping [-c ] [-i ] 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 ] -h

Copy the file at to the host whose IP address is identified by . Other options: -f The file will be saved with the same name on the host unless unless is provided. -b|-n Selects either binary ("octect") 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 Remove the specified name from the mounted file system. Recall that NuttX uses a pseudo filesystem 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 filesystem. 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 Remove the specified directory from the mounted file system. Recall that NuttX uses a pseudo filesystem 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 filesystem. 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 Set the environment variable to the sting . For example, nsh> echo $foobar nsh> set foobar foovalue nsh> echo $foobar foovalue nsh> o sh Execute the sequence of NSH commands in the file referred to by . o sleep Pause execution (sleep) of seconds. o unset Remove the value associated with the environment variable . Example: nsh> echo $foobar foovalue nsh> unset foobar nsh> echo $foobar nsh> o usleep Pause execution (sleep) of microseconds. o wget [-o ] Use HTTP to copy the file at to the current directory. Options: -o The file will be saved relative to the current working directory and with the same name as on the HTTP server unless is provided. o xd

Dump bytes of data from 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 cat CONFIG_NFILE_DESCRIPTORS > 0 cd !CONFIG_DISABLE_ENVIRON && CONFIG_NFILE_DESCRIPTORS > 0 cp CONFIG_NFILE_DESCRIPTORS > 0 dd CONFIG_NFILE_DESCRIPTORS > 0 echo -- exec -- exit -- free -- get CONFIG_NET && CONFIG_NET_UDP && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NET_BUFSIZE >= 558 (see note 1) help -- ifconfig CONFIG_NET kill !CONFIG_DISABLE_SIGNALS losetup !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 ls CONFIG_NFILE_DESCRIPTORS > 0 mb,mh,mw --- mkdir !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_WRITABLE (see note 4) 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) ping CONFIG_NET && CONFIG_NET_ICMP && CONFIG_NET_ICMP_PING && !CONFIG_DISABLE_CLOCK && !CONFIG_DISABLE_SIGNALS ps -- put CONFIG_NET && CONFIG_NET_UDP && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_NET_BUFSIZE >= 558 (see note 1,2) pwd !CONFIG_DISABLE_ENVIRON && CONFIG_NFILE_DESCRIPTORS > 0 rm !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_WRITABLE (see note 4) rmdir !CONFIG_DISABLE_MOUNTPOINT && CONFIG_NFILE_DESCRIPTORS > 0 && CONFIG_FS_WRITABLE (see note 4) 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 usleep !CONFIG_DISABLE_SIGNALS get CONFIG_NET && CONFIG_NET_TCP && CONFIG_NFILE_DESCRIPTORS > 0 xd --- * NOTES: 1. Because of hardware padding, the actual buffersize required for put and get operations size may be larger. 2. Special TFTP server start-up optionss 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 filesystem 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 writable filesystem 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_CAT, CONFIG_NSH_DISABLE_CD, CONFIG_NSH_DISABLE_CP, CONFIG_NSH_DISABLE_DD, 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_IFCONFIG, CONFIG_NSH_DISABLE_KILL, CONFIG_NSH_DISABLE_LOSETUP, CONFIG_NSH_DISABLE_LS, 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_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_USLEEP, CONFIG_NSH_DISABLE_WGET, CONFIG_NSH_DISABLE_XD NSH-Specific Configuration Settings ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The behavior of NSH can be modified with the following settings in the configs//defconfig file: * CONFIG_NSH_BUILTIN_APPS Support external registered, "named" 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 filesystem). 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' * CONFIG_NSH_LINELEN The maximum length of one command line and of one output line. Default: 80 * CONFIG_NSH_STACKSIZE The stack size to use when spawning new threads or tasks. Such new threads are generated when a command is executed in background or as new TELNET connections are established. * 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_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 filesystem 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. * CONFIG_NSH_CONDEV If CONFIG_NSH_CONSOLE is set to 'y', then CONFIG_NSH_CONDEV may also be set to select the serial device used to support the NSH console. This should be set to 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: 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 set your terminal program to account for this. And (2) input is not automatically echoed so you will have to turn local echo on. * 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. 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. 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_BUFSIZE=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). 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.