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shift(1) [linux man page]

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

NAME

       shift - shift positional parameters

SYNOPSIS

       shift [n]

DESCRIPTION

       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

       None.

OPERANDS

       See the DESCRIPTION.

STDIN

       Not used.

INPUT FILES

       None.

ENVIRONMENT VARIABLES

       None.

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

       The exit status is >0 if n>$#; otherwise, it is zero.

CONSEQUENCES OF ERRORS

       Default.

       The following sections are informative.

APPLICATION USAGE

       None.

EXAMPLES

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

RATIONALE

       None.

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, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications 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 Standard, 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								  SHIFT(P)

Check Out this Related Man Page

EVAL(P) 						     POSIX Programmer's Manual							   EVAL(P)

NAME

       eval - construct command by concatenating arguments

SYNOPSIS

       eval [argument ...]

DESCRIPTION

       The  eval  utility  shall  construct a command by concatenating arguments together, separating each with a <space>. The constructed command
       shall be read and executed by the shell.

OPTIONS

       None.

OPERANDS

       See the DESCRIPTION.

STDIN

       Not used.

INPUT FILES

       None.

ENVIRONMENT VARIABLES

       None.

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 there are no arguments, or only null arguments, eval shall return a zero exit status; otherwise, it shall return the exit status of  the
       command defined by the string of concatenated arguments separated by <space>s.

CONSEQUENCES OF ERRORS

       Default.

       The following sections are informative.

APPLICATION USAGE

       None.

EXAMPLES

	      foo=10 x=foo
	      y='$'$x
	      echo $y
	      $fooeval y='$'$x
	      echo $y
	      10

RATIONALE

       None.

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, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications 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 Standard, 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								   EVAL(P)
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