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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 differ (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  correspond-
       ing  to  the specified names, which shall cause them to be in the envi-
       ronment 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 POSIX.1-2008, 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. If a variable
       assignment precedes the command name of export but that variable is not
       also listed as an operand of export, then that variable shall be set in
       the current shell execution environment after  the  completion  of  the
       export  command,  but it is unspecified whether that variable is marked
       for export.
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 S
       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-file
           unset 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 implemen-
       tations. 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
       Section 2.14, Special Built-In Utilities
       The Base Definitions volume of POSIX.1-2008, Section 12.2, Utility Syn-
       tax Guidelines
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal 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 Standard
       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.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                           EXPORT(1P)