touch(1)						      General Commands Manual							  touch(1)

NAME

       touch - Updates file access and modification times

SYNOPSIS

       touch [-acfm] [-r reference_file | -t time] file...

       The  following  older  syntax  is  now  maintained  for backward compatibility, but may be withdrawn in future issues: touch [-acfm] [time]
       file...

STANDARDS

       Interfaces documented on this reference page conform to industry standards as follows:

       touch:  XCU5.0

       Refer to the standards(5) reference page for more information about industry standards and associated tags.

OPTIONS

       Changes only the access time.  Suppresses the creation of the file.  [Tru64 UNIX]  Attempts to force the touch in spite of read	and  write
       permissions on a file.  The -f option is actually a dummy option; it is not used by the touch code, but is recognized by getopt().  Changes
       only the modification time.  Uses the time of the file named by the pathname reference_file instead of the current time. You cannot use	-r
       and -t together.  Uses the specified time instead of the current time.

	      The time argument is a decimal number in the following form: [[CC]YY]MMDDhhmm[.SS]

	      The  paired decimal numbers in the preceding syntax line represent the following: The first two digits of the year (the century) The
	      second two digits of the year (00-99) The month of the year (01-12) The day of the month (01-31) The hour of  the  day  (00-23)  The
	      minute of the hour (00-59) The second of the minute (00-61)

	      Both  CC	and  YY  are  optional.   If  neither is specified, the current year is assumed.  If YY is specified, but CC is not, CC is
	      derived as follows:

	      If YY is 69-99, CC is 19.

	      If YY is 00-68, CC is 20.

	      The resulting time is affected by the value of the TZ environment variable.  If the resulting time value precedes the  Epoch,  touch
	      exits immediately with an error status.  The range of valid times past the Epoch extends to at least midnight 1 January 2000 UCT.

	      The  range for SS is 00-61 rather than 00-59 because of leap seconds.  If SS is 60 or 61, and the resulting time, as affected by the
	      TZ environment variable, does not refer to a leap second, the resulting time is one or two seconds after a time where SS is 59.	If
	      SS is not given a value, it is assumed to be 0 (zero).

       If neither the -a option nor the -m options are specified, touch behaves as if you have specified both options.

OPERANDS

       The file for which times should be modified, or which should be created.

	      In the obsolescent version, if both the -r and -t options are omitted, and if the first file parameter is an eight or ten digit dec-
	      imal integer, it is interpreted as a time parameter.

	      The format for the time parameter in the obsolesent syntax is MMDDhhmm[YY]

DESCRIPTION

       The touch command updates the access and modification times of each file or directory named to the one specified on the command line or	to
       the  current  time if you do not specify a time.  You can specify the time with -t or by the time of the reference file with the -r option.
       If you do not specify a time, touch uses the current time.  If you specify a file that does not exist, touch creates a file with that  name
       unless you request otherwise with the -c option.

       The  LC_TIME environment variable, if defined, specifies the order of month and day in the date specification and of hour and minute in the
       time specification.  Otherwise, these orders default to MMdd and hhmm.  The format for the time argument is MMddhhmm[yy].

       The obsolescent format for the time argument is MMddhhmm[YY].

NOTES

       The obsolescent version may be withdrawn from future versions of the XCU5.0 standards.  The -r or -t options should be used.

EXIT STATUS

       The following exit values are returned: Successful completion.  [Tru64 UNIX]  The number of files whose times  could  not  be  successfully
       modified (including files that did not exist and were not created).

       When  the  -c  option is specified, files are suppressed purposely, an error does not occur and a message is not written to standard error.
       The exit status returns zero (0) for success.

EXAMPLES

       To update the access and modification times of a file, enter: touch program.c

	      This sets the last access and last modification times of program.c to the current date and time.	If program.c does not exist, touch
	      creates  an  empty  file	with  that name.  To avoid creating a new file, enter: touch -c  program.c To update only the modification
	      time, enter: touch -m *.o

	      This updates only the last modification times of the files in the current directory that end with touch command  is  often  used	in
	      this  way  to  alter the results of the make command.  To explicitly set the access and modification times, enter: touch -c 02171425
	      program.c

	      This sets the access and modification dates to 14:25 (2:25 p.m.) February 17 of the current year.  (This assumes that you are  using
	      the  default  format.)   To touch a file with a numeric file name, include its full pathname or precede it with not mistaken for the
	      time argument. For example, to touch the file 123.abc enter: touch -c ./123.abc

ENVIRONMENT VARIABLES

       The following environment variables affect the execution of touch: Provides a default value for the internationalization variables that are
       unset or null. If LANG is unset or null, the corresponding value from the default locale is used.  If any of the internationalization vari-
       ables contain an invalid setting, the utility behaves as if none of the variables had been defined.  If set to a  non-empty  string  value,
       overrides  the  values of all the other internationalization variables.	Determines the locale for the interpretation of sequences of bytes
       of text data as characters (for example, single-byte as opposed to multibyte characters in arguments).  Determines the locale for the  for-
       mat  and  contents  of  diagnostic  messages written to standard error.	[Tru64 UNIX]  This environment variable, if defined, specifies the
       order of month and day in the date specification and of hour and minute in the time specification.  Otherwise, these orders default to MMdd
       and  hhmm.   The format for the time argument is MMddhhmm[yy].  Determines the location of message catalogues for the processing of LC_MES-
       SAGES.  Determines the time zone to be used for interpreting the time specification.

SEE ALSO

       Commands:  date(1)

       Functions:  creat(2), utime(2)

       Files:  locale(4)

       Standards:  standards(5)

																	  touch(1)