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

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

       shift — shift positional parameters

SYNOPSIS         top

       shift [n]

DESCRIPTION         top

       The positional parameters shall be shifted. Positional parameter 1
       shall be assigned the value of parameter (1+n), parameter 2 shall be
       assigned the value of parameter (2+n), and so on. The parameters
       represented by the numbers "$#" down to "$#−n+1" shall be unset, and
       the parameter '#' is updated to reflect the new number of positional
       parameters.
       The value n shall be an unsigned decimal integer less than or equal
       to the value of the special parameter '#'.  If n is not given, it
       shall be assumed to be 1. If n is 0, the positional and special
       parameters are not changed.

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

       If the n operand is invalid or is greater than "$#", this may be
       considered a syntax error and a non-interactive shell may exit; if
       the shell does not exit in this case, a non-zero exit status shall be
       returned. Otherwise, zero shall be returned.

CONSEQUENCES OF ERRORS         top

       Default.
       The following sections are informative.

APPLICATION USAGE         top

       None.

EXAMPLES         top

       $ set a b c d e
       $ shift 2
       $ echo $*
       c d e

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       Section 2.14, Special Built-In Utilities

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                           SHIFT(1P)