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return(1p) — Linux manual page

PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT 

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

PROLOG top 

       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 top 

       return — return from a function or dot script

SYNOPSIS top 

       return [n]

DESCRIPTION top 

       The return utility shall cause the shell to stop executing the
       current function or dot script. If the shell is not currently
       executing a function or dot script, the results are unspecified.

OPTIONS top 

       None.

OPERANDS top 

       See the DESCRIPTION.

STDIN top 

       Not used.

INPUT FILES top 

       None.

ENVIRONMENT VARIABLES top 

       None.

ASYNCHRONOUS EVENTS top 

       Default.

STDOUT top 

       Not used.

STDERR top 

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES top 

       None.

EXTENDED DESCRIPTION top 

       None.

EXIT STATUS top 

       The value of the special parameter '?'  shall be set to n, an
       unsigned decimal integer, or to the exit status of the last command
       executed if n is not specified. If the value of n is greater than
       255, the results are undefined. When return is executed in a trap
       action, the last command is considered to be the command that
       executed immediately preceding the trap action.

CONSEQUENCES OF ERRORS top 

       Default.

       The following sections are informative.

APPLICATION USAGE top 

       None.

EXAMPLES top 

       None.

RATIONALE top 

       The behavior of return when not in a function or dot script differs
       between the System V shell and the KornShell. In the System V shell
       this is an error, whereas in the KornShell, the effect is the same as
       exit.

       The results of returning a number greater than 255 are undefined
       because of differing practices in the various historical
       implementations. Some shells AND out all but the low-order 8 bits;
       others allow larger values, but not of unlimited size.

       See the discussion of appropriate exit status values under exit(1p).

FUTURE DIRECTIONS top 

       None.

SEE ALSO top 

       Section 2.9.5, Function Definition Command, Section 2.14, Special
       Built-In Utilities, dot(1p)

COPYRIGHT top 

       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 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 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.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                          RETURN(1P)

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