checking if a file is over X minutes old 1

[Larshg]

Hi

I need to make a script that can check if a file is over X number og minutes old. It has to account for midninght and newyears. I'v tryede making it in ksh but couldn't figure out how to get it to work probaly, and someone told me that perl would be mutch better at it. - I don't know thats mutch about pearl.

I working on a HP-unix server.

/Larshg

 

[rosenk]

You can use [tt]stat $file[/tt] to get a list of various information about [tt]$file[/tt]. The 10th element is the last modified time in seconds since the epoch. (9th is last access time in seconds since, 11th is inode change time in seconds since the epoch [which should be similar to creation time, but is not actually... I don't know the precise differences.])

[tt]if ((time - (stat $file)[9]) > ($minutes * 60)) {
print "File was last modified more than $minutes ago\n";
}[/tt]

 

[Larshg]

Thanks it works great

Can you tell me if I need to worry about midnight or newyears? - are there any senarios where this script will have problems?

/Lars

 

[rosenk]

No problems with midnight or New Years, since the values are just seconds since January 1, 1970 (or something along those lines.)

The only potential problem would be related to daylight savings time. When the clock goes back an hour, the file would be an hour younger than it was (or an hour older when the clock goes the other way.)

 

[MikeLacey]

Rosenk,

Actually - I think your code will work just fine over a daylight saving time transition. Dates and times in UNIX are stored as the number of seconds since 1st Jan 1970, without regard to daylight saving. Mike

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