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

NAME
       colon - null utility

SYNOPSIS
       : [argument ...]

DESCRIPTION
       This  utility shall only expand command arguments. It is used when a command is needed, as
       in the then condition of an if command, but nothing is to be done by the command.

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
       Zero.

CONSEQUENCES OF ERRORS
       Default.

       The following sections are informative.

APPLICATION USAGE
       None.

EXAMPLES
	      : ${X=abc}
	      if     false
	      then   :
	      else   echo $X
	      fi
	      abc

       As with any of the special built-ins, the null utility can also have variable  assignments
       and redirections associated with it, such as:

	      x=y : > z

       which  sets  variable  x  to  the value y (so that it persists after the null utility com-
       pletes) and creates or truncates file z.

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 Technology -- 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 orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003					 COLON(P)
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