help — Display help on built in commands
help [command]
Without a parameter this command lists the in-built
commands understood by the shell. Specifying a command name
prints a brief help message for that command which is
typically the same as using the --help
option.
Example 9.3. Using the help command
This shows the help command being used to get help on
the help command itself, it then shows obtaining help on
the sh command and obtaining the same
information with the --help
option.
>help
Internal commands are:
sh autoboot sbcd bast-hdlcd pic-wr pic-rd
bast-at2 bast-at dmcfg-rd dmcfg-wr pmu shadow
mii ifconfig set [ test console
display file hwinfo wrout version nvclear
nvunset nvsave nvshow nvset uname sum
tasks sleep showhz sysmsg setopt showargs
setargs reset memset meminfo peek poke
modules ls lsfs help echo dumpfile
dump cat cp cd pwd boot
load history vtp5 vtp4 vtp3 vtp2
vtp1 sysspeed settime setdate devls date
Use:
help <command> to get brief explanation
<command> --help for command usage (if available)
>help help
Help on help:
Lists available commands, Optional arg gives help on specific command.
Please report bugs to <support@simtec.co.uk>
>help sh
Help on sh:
Usage: sh [OPTION] [FILE]
start a shell.
-i start an interactive shell
--help display this help and exit
--version output version information and exit
Please report bugs to <support@simtec.co.uk>
>sh --help
Usage: sh [OPTION] [FILE]
start a shell.
-i start an interactive shell
--help display this help and exit
--version output version information and exit
Please report bugs to <support@simtec.co.uk>
>The Example 3.2, “Getting help on the uname command” is another example of using the help command.