mtime, ctime, and atime Post: 302134305

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Top Forums UNIX for Beginners Questions & Answers Answers to Frequently Asked Questions Tips and Tutorials mtime, ctime, and atime Post 302134305 by Perderabo on Thursday 30th of August 2007 09:13:22 AM

08-30-2007

Administrator Emeritus

Using perl to display the file timestamps

The ls program will display mtime if you use "ls -l". And you can get atime or ctime with "ls -lu" or "ls -lc". But ls uses a strange format. It displays the month and day in all cases. If the timestamp is recent, it also displays hour and minute. If the timestamp is older than 6 months, it display the year instead of hour and minute. A clever script can reformat this to year, month, day, hour, and minute. But ls will not display the seconds. The gnu version of ls (which is usually the only version on linux) does have extended options like --fulltime. But these extended options are non-standard and won't be available on other versions of Unix.

The perl language is also non-standard, but perl tends to be available on most versions of unix. For example, a version of perl is supplied with HP-UX and Solaris. Perl can easily display the timestamps of files. Here are some perl one-liners to display atime, mtime, and ctime.

Code:

$ echo hello > testfile ; date
Thu Aug 30 08:31:57 EDT 2007
$ chmod 700 testfile ; date
Thu Aug 30 08:32:48 EDT 2007
$ cat testfile ; date
hello
Thu Aug 30 08:33:30 EDT 2007
$
$
$
$
$ perl -e '@d=localtime ((stat(shift))[8]); printf "%4d%02d%02d%02d%02d%02d\n", $d[5]+1900,$d[4]+1,$d[3],$d[2],$d[1],$d[0]' testfile
20070830083330
$ perl -e '@d=localtime ((stat(shift))[9]); printf "%4d%02d%02d%02d%02d%02d\n", $d[5]+1900,$d[4]+1,$d[3],$d[2],$d[1],$d[0]' testfile
20070830083157
$ perl -e '@d=localtime ((stat(shift))[10]); printf "%4d%02d%02d%02d%02d%02d\n", $d[5]+1900,$d[4]+1,$d[3],$d[2],$d[1],$d[0]' testfile
20070830083248
$

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LEARN ABOUT PHP

get_midi_length

get_midi_length(3alleg4)					  Allegro manual					  get_midi_length(3alleg4)

NAME

       get_midi_length - Determines the total playing time of a midi, in seconds. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       int get_midi_length(MIDI *midi);

DESCRIPTION

       This function will simulate playing the given MIDI, from start to end, to determine how long it takes to play. After calling this function,
       midi_pos will contain the negative number of beats, and midi_time the length of the midi, in seconds.

       Note that any currently playing midi is stopped when you call this function.  Usually you would call it before play_midi, to get the length
       of the midi to be played, like in this example:

	  length = get_midi_length(my_midi);
	  play_midi(my_midi);
	  do {
	     pos = midi_time;
	     textprintf_ex(screen, font, 0, 0, c, -1, "%d:%02d / %d:%02d
",
		pos / 60, pos % 60, length / 60, length % 60);
	     rest(100);
	  } while(pos <= length);

RETURN VALUE

       Returns the value of midi_time, the length of the midi.

SEE ALSO

       load_midi(3alleg4), midi_time(3alleg4), midi_pos(3alleg4), exmidi(3alleg4)

Allegro 							   version 4.4.2					  get_midi_length(3alleg4)