List of Korn shell or POSIX shell special built-in commands
Special commands are built into the Korn shell and POSIX shell and executed in the shell process.
| Item | Description |
|---|---|
| : (colon) | Expands only arguments. |
| . (dot) | Reads a specified file and then executes the commands. |
| break | Exits from the enclosing for, while, until, or select loop, if one exists. |
| continue | Resumes the next iteration of the enclosing for, while, until, or select loop. |
| eval | Reads the arguments as input to the shell and executes the resulting command or commands. |
| exec | Executes the command specified by the Argument parameter, instead of this shell, without creating a new process. |
| exit | Exits the shell whose exit status is specified by the n parameter. |
| export | Marks names for automatic export to the environment of subsequently executed commands. |
| newgrp | Equivalent to the exec/usr/bin/newgrp [Group ...] command. |
| readonly | Marks the specified names read-only. |
| return | Causes a shell to return to the invoking script. |
| set | Unless options or arguments are specified, writes the names and values of all shell variables in the collation sequence of the current locale. |
| shift | Renames positional parameters. |
| times | Prints the accumulated user and system times for both the shell and the processes run from the shell. |
| trap | Runs a specified command when the shell receives a specified signal or signals. |
| typeset | Sets attributes and values for shell parameters. |
| unset | Unsets the values and attributes of the specified parameters. |