NAME

touch — change file access and modification times

SYNOPSIS

DESCRIPTION

touch changes the date modification and access times on each file it is given.

-a

Change the access time, no changes to modification time unless -m is also given.

-c

Do not create file.

-f

Ignored. coreutils and BusyBox never supported it, OpenBSD removed it in 2005, NetBSD in 2011, FreeBSD in 2012.

-d isotime

Should be formatted either with a leading @ (at) symbol followed by the Unix timestamp (number of seconds before and after 1970-01-01 00:00:00Z), for example ‘@1698791420’ corresponds to 2023-10-31 23:30:20 UTC

Or as ‘YYYY-MM-DDThh:mm:SS[frac][tz]’, where:

‘YYYY-MM-DD’

Corresponds to %Y-%m-%d of strptime(3).

‘T’

Is either ‘T’ or a space.

‘[frac]’

Is either empty, or fractional seconds starting with either a comma (,) or a period (.).

‘[tz]’

When empty it corresponds to local time. Otherwise it can be an UTC offset in the format ‘[+-]HH:?MM’ or the letter "Z", signifying UTC.

Some examples:

• ‘2003-06-02T13:37:42.713Z’
• ‘1971-01-02T03:04:05.678+0900’

-c

Ignored.

-h

Do not follow symlinks.

-m

Change the modification time, no changes to access time unless -a is also given.

-t datetime

Use the specified datetime instead of the current time, with the form [[CC]YY]MMDDhhmm[.SS] where:

‘CC’

Corresponds to the first 2 digits of the year, aka %C

‘YY’

Corresponds to the last 2 digits of the year, aka %y

‘MMDDhhmm’

Corresponds to month, day, hours, minutes aka %m%d%H%M

‘.SS’

Corresponds to the seconds

For example: ‘200306021337.42’

-r ref_file

Use the corresponding times of the file at ref_file instead of the current time.

EXIT STATUS

The touch utility exits 0 on success, and >0 if an error occurs. Note: Will exit with failure when -c is given but the file doesn't exists.

SEE ALSO

stat(1), futimens(3), strptime(3)

STANDARDS

touch should be compliant with the IEEE Std 1003.1-2024 (“POSIX.1”) specification.

-h and -f are extensions.

AUTHORS

Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>