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touch system



touch -- change file access and modification times


touch files


List of files to be created or touched.
create = yes
If enabled, the file will be created as a zero-length text file if it doesn't already exist.
atime = yes
Change the access time of the file. Will not change the modification time unless mtime is also set.
mtime = yes
Change the modification time of the file. Will not change the access time unless atime is also set.
time = ""
Time and date to set for the file. The format of this string may be any of DD/MM/YY or CCYY-MM-DD (in which case time is assumed to be midnight of that day), or CCYY-MM-DDTHH:MM:SS[.SSS...] to specify both date and time. If not specified, the current system time is used unless the ref_file parameter is set. If specified, ref_file will be ignored.
ref_file = ""
Use the corresponding times of the specified file for modifying the times of the input_files . If not specified, the current time is used unless the time parameter is set.
verbose = no
Print verbose output of the files and times being reset.


The touch task sets the access and modification times of each file in the files list. The file will be created if it does not already exist when the create parameter is set. The time used can be specified by time parameter or by the corresponding fields of the file specified by ref_file , otherwise the current system time will be used. The task will update both the modification and access times of the file unless disabled by the atime or mtime parameter.


1. Update the times of all SPP source files in the current directory:

cl> touch *.x

2. Create an empty file on a remode node:

cl> touch ursa!/data/trigger_file

3. Reset the file modification time to 2:33:45 pm on June 5, 2003:

cl> touch nite1.fits time="2003-06-05T14:23:45"

4. Reset the file modification time to match dev$hosts:

cl> touch nite1.fits ref_file=dev$hosts


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