dot man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

dot ā€” execute commands in the current environment


. file


The shell shall execute commands from the file in the current environment.

If file does not contain a <slash>, the shell shall use the search path specified by PATH to find the directory containing file. Unlike normal command search, however, the file searched for by the dot utility need not be executable. If no readable file is found, a non-interactive shell shall abort; an interactive shell shall write a diagnostic message to standard error, but this condition shall not be considered a syntax error.




See the Description.


Not used.

Input Files

See the Description.

Environment Variables

See the Description.

Asynchronous Events



Not used.


The standard error shall be used only for diagnostic messages.

Output Files


Extended Description


Exit Status

If no readable file was found or if the commands in the file could not be parsed, and the shell is interactive (and therefore does not abort; see Section 2.8.1, Consequences of Shell Errors), the exit status shall be non-zero. Otherwise, return the value of the last command executed, or a zero exit status if no command is executed.

Consequences of Errors


The following sections are informative.

Application Usage



cat foobar
foo=hello bar=world
. ./foobar
echo $foo $bar
hello world


Some older implementations searched the current directory for the file, even if the value of PATH disallowed it. This behavior was omitted from this volume of POSIX.1-2008 due to concerns about introducing the susceptibility to trojan horses that the user might be trying to avoid by leaving dot out of PATH.

The KornShell version of dot takes optional arguments that are set to the positional parameters. This is a valid extension that allows a dot script to behave identically to a function.

Future Directions


See Also

Section 2.14, Special Built-In Utilities, return

Referenced By


2013 IEEE/The Open Group POSIX Programmer's Manual