touch(1) touch(1)
NAME
touch - update access and modification times of a file
SYNOPSIS
touch [-amc] [-r ref_file | -t time] file ...
touch [-amc] [mmddhhmm[yy]] file ...
DESCRIPTION
touch causes the access and modification times of each
argument to be updated. The file name is created if it does
not exist. If no time is specified the current time is used.
[See date(1) for a description of the second synopsis' time
format.]
OPTIONS
-a Update only the access time.
-m Update only the modification time.
If neither -a nor -m is specified, the effect is the
same as -am.
-c Silently prevent touch from creating the file if it did
not previously exist.
-r ref_file
Use the corresponding time of ref_file instead of the
current time.
-t time
Use time instead of the current time. time is a decimal
number of the form:
[[CC]YY]MMDDhhmm[.SS]
where each two digits represent the following:
MM month of the year (01-12)
DD day of the month (01-31)
hh hour of the day (00-23)
mm minute of the hour (00-59)
CC first two digits of the year (the century)
YY second two digits of the year
SS second of the minute (0-61)
CC and YY are optional. If neither is given, the
current year is assumed. If YY is specified, but CC is
not, CC is derived as follows:
Copyright 1994 Novell, Inc. Page 1
touch(1) touch(1)
If YY is: CC becomes:
_______________________
69-99 19
00-68 20
The range for SS is (00-61), 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 shall be one or two seconds
after a time where SS is 59. If SS is not given it is
assumed to be zero.
DIAGNOSTICS
The return code from touch is the number of files for which
the times could not be successfully modified (including files
that did not exist and were not created).
If the POSIX2 environment variable is set and exported, files
that did not exist and were not created are not considered to
be errors, and will not increment the return code.
FILES
/usr/lib/locale/locale/LC_MESSAGES/uxcore.abi
language-specific message file [See LANG on environ
(5).]
REFERENCES
date(1), utime(2)
NOTICES
Users familiar with the BSD environment will find that the -f
option is accepted, but ignored. The -f option is unnecessary
since touch will succeed for all files owned by the user
regardless of the permissions on the files.
touch assumes that an all numeric entry is a date and so will
not update the times for a file when an all numeric filename
is specified.
The -t time option should be used in preference to the second
synopsis usage, since the second synopsis may not be supported
in future releases.
Copyright 1994 Novell, Inc. Page 2