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



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

NAME
       export - set the export attribute for variables

SYNOPSIS
       export name[=word]...

       export -p


DESCRIPTION
       The  shell  shall  give the export attribute to the variables corresponding to the specified names, which shall
       cause them to be in the environment of subsequently executed commands. If the name of a variable is followed by
       = word, then the value of that variable shall be set to word.

       The  export  special  built-in shall support the Base Definitions volume of IEEE Std 1003.1-2001, Section 12.2,
       Utility Syntax Guidelines.

       When -p is specified, export shall write to the standard output the names and values of all exported variables,
       in the following format:


              "export %s=%s\n", <name>, <value>

       if name is set, and:


              "export %s\n", <name>

       if name is unset.

       The  shell  shall format the output, including the proper use of quoting, so that it is suitable for reinput to
       the shell as commands that achieve the same exporting results, except:

        1. Read-only variables with values cannot be reset.


        2. Variables that were unset at the time they were output need not be reset to the unset state if a  value  is
           assigned  to  the  variable  between the time the state was saved and the time at which the saved output is
           reinput to the shell.


       When no arguments are given, the results are unspecified.

OPTIONS
       See the DESCRIPTION.

OPERANDS
       See the DESCRIPTION.

STDIN
       Not used.

INPUT FILES
       None.

ENVIRONMENT VARIABLES
       None.

ASYNCHRONOUS EVENTS
       Default.

STDOUT
       See the DESCRIPTION.

STDERR
       The standard error shall be used only for diagnostic messages.

OUTPUT FILES
       None.

EXTENDED DESCRIPTION
       None.

EXIT STATUS
       Zero.

CONSEQUENCES OF ERRORS
       Default.

       The following sections are informative.

APPLICATION USAGE
       None.

EXAMPLES
       Export PWD and HOME variables:


              export PWD HOME

       Set and export the PATH variable:


              export PATH=/local/bin:$PATH

       Save and restore all exported variables:


              export -p > temp-fileunset a lot of variables... processing. temp-file

RATIONALE
       Some historical shells use the no-argument case as the functional equivalent of what is required here with  -p.
       This  feature  was  left  unspecified because it is not historical practice in all shells, and some scripts may
       rely on the now-unspecified results on their implementations. Attempts to specify the -p output as the  default
       case  were  unsuccessful in achieving consensus. The -p option was added to allow portable access to the values
       that can be saved and then later restored using; for example, a dot script.

FUTURE DIRECTIONS
       None.

SEE ALSO
       Special Built-In Utilities

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Stan-
       dard  for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifica-
       tions Issue 6, Copyright (C) 2001-2003 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 Stan-
       dard, 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 .



IEEE/The Open Group                  2003                           EXPORT(1P)