Name

help — Display help on built in commands

Synopsis

help [command]

Options

command

inbuilt command name

Description

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 33. 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 3.5, “Getting help on the uname command” is another example of using the help command.