DOT
Section: POSIX Programmer's Manual (1P)
Updated: 2017
Page Index
PROLOG
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.
NAME
dot
--- execute commands in the current environment
SYNOPSIS
. file
DESCRIPTION
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.
OPTIONS
None.
OPERANDS
See the DESCRIPTION.
STDIN
Not used.
INPUT FILES
See the DESCRIPTION.
ENVIRONMENT VARIABLES
See the DESCRIPTION.
ASYNCHRONOUS EVENTS
Default.
STDOUT
Not used.
STDERR
The standard error shall be used only for diagnostic messages.
OUTPUT FILES
None.
EXTENDED DESCRIPTION
None.
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
Default.
The following sections are informative.
APPLICATION USAGE
None.
EXAMPLES
cat foobar
foo=hello bar=world
. ./foobar
echo $foo $bar
hello world
RATIONALE
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.1-2017 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
None.
SEE ALSO
Section 2.14,
Special Built-In Utilities,
return
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .