posix man page for dot

DOT(1P) 						     POSIX Programmer's Manual							   DOT(1P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing 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-inter-
       active shell shall abort; an interactive shell shall write a diagnostic message to standard error, but this condition shall not be  consid-
       ered 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.1-2008 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
       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, 2013 Edition, Standard for Information Technol-
       ogy  --	Portable  Operating  System  Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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 Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/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 .

IEEE
/The Open Group						       2013								   DOT(1P)