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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
       software installation option.  Refer  to  for  information  on  how  to
       install optional software.

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

       touch is valuable when used in conjunction  with  make(1),  where,  for
       instance,  you might want to force a complete rebuild of a program com-
       posed 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
       corresponding .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 permis-
              sions 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
       current 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)