9.2.1 List of standard shell commands
The standard shell commands include special built-in commands and regular built-in commands.
Command name |
Overview |
---|---|
. |
Executes a shell script. |
: |
Expands arguments and returns 0 as the return code. |
break |
Exits from a loop. |
continue |
Interrupts loop processing and returns to the beginning of the next cycle of the loop. |
eval |
Concatenates arguments into a command that it executes. |
exec |
Executes a specified command and then exits. |
exit |
Exits the shell. |
export |
Exports shell variables. |
readonly |
Sets the read-only attribute for variables or displays all read-only variables. |
return |
Returns from a function or an external script. |
set |
Sets shell options, creates an array, or displays variable values. |
shift |
Shifts the run-time parameters. |
trap |
Specifies the action when signals and forced termination requests are received. |
typeset |
Declares explicitly the attributes and values of variables and functions. |
unset |
Unsets variable values and attributes. |
Command name |
Overview |
---|---|
alias |
Defines aliases. |
builtin |
Executes a built-in command. |
cd |
Changes the current directory. |
command |
Executes a built-in command or external command. |
echo |
Outputs what is specified in arguments to the standard output. |
false |
Returns 1 as the return code. |
getopts |
Parses option arguments. |
kill |
Sends a signal to processes. |
let |
Evaluates the values of arithmetic expressions. |
|
Outputs what is specified in the arguments to the standard output. |
pwd |
Outputs the path of the current directory. |
read |
Reads from the standard input and stores the input in shell variables. |
test |
Determines the value of a conditional expression. |
times |
Displays the amount of CPU time used by the shell. |
true |
Returns 0 as the return code. |
ulimit (UNIX only) |
Sets or displays information about limits on system resources. |
umask (UNIX only) |
Sets or displays the file mode creation mask. |
unalias |
Removes alias definitions. |
wait |
Waits for child processes to complete. |
whence |
Displays how specified character strings would be interpreted if used as commands. |