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TOUCH(1V)							       TOUCH(1V)

NAME
     touch - update the access and modification times of a file

SYNOPSIS
     touch [ -c ] [ -f ] filename...

SYSTEM V SYNOPSIS
     /usr/5bin/touch [ -acm ] [ date-time ] filename...

AVAILABILITY
     The  System  V version of this command is available with the System V soft-
     ware installation option.	Refer to for information on how to  install  op-
     tional software.

DESCRIPTION
     touch  sets  the access and modification times of each argument to the cur-
     rent time.  A file is created if it does not already exist.

     touch is valuable when used in conjunction with  make(1),	where,	for  in-
     stance, you might want to force a complete rebuild of a program composed of
     many pieces.  In such a case, you might type:

		   example% touch *.c
		   example% make

     make(1) would then see that all the .c files were more recent than the cor-
     responding .o files, and would start the compilation from scratch.

OPTIONS
     -c     Do not create filename if it does not exist.

     -f     Attempt to force the touch in spite of read and write permissions on
	    filename.

SYSTEM V OPTIONS
     Options must be grouped to form the first argument.  The date-time argument
     takes the form:

	    mmddhhmm[yy]

     and  updates  the modification time to that specified, rather than the cur-
     rent time.  The first mm is the month, dd is the day of the  month,  hh  is
     the  hour,  and the second mm is the minute.  If yy is specified, it is the
     last two digits of the year.  If omitted, the current year is assumed.

     -a     Update only the access time.

     -c     Do not create filename if it does not exist.

     -m     Update only the modification time.

SEE ALSO
     make(1), utimes(2)

BUGS
     It is difficult to touch a file whose name consists entirely of  digits  in
     the  System  V touch, as it will interpret the first such non-flag argument
     as a time.  You must ensure that there is a character in the name which  is
     not a digit, by specifying it as ./name rather than name.

				19 September 1989		       TOUCH(1V)
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