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watching a file

Hey everyone,

Is there a way to "watch" a file for changes? I know I could poll the
file every few seconds and check to see if the buffer has changed but
is there a cleaner way?

thanks!

Ben
Nov 14 '05 #1
5 1614
"Benjamin D. LeMasurier" <ui*****@uidzer 0.org> wrote in message
news:9c******** *************** ***@posting.goo gle.com...
Hey everyone,

Is there a way to "watch" a file for changes?
I assume you mean changes made by some other process.
Otherwise your program already 'knows' when it changes
things.
I know I could poll the
file every few seconds and check to see if the buffer has changed but
is there a cleaner way?


Depending upon your operating system, probably yes. But
standard C doesn't recognize the notion of multiple processes,
shared files, etc. Those issues are the domain of the operating
system. Ask in a forum which discuss your host platform.

-Mike
Nov 14 '05 #2

"Benjamin D. LeMasurier" <ui*****@uidzer 0.org> wrote in message
news:9c******** *************** ***@posting.goo gle.com...
Hey everyone,

Is there a way to "watch" a file for changes? I know I could poll the
file every few seconds and check to see if the buffer has changed but
is there a cleaner way?
Depends on your OS. AFAIK, there is no standard 'C' way to do it. On a POSIX
system, stat() and check atime.
thanks!

Ben

Nov 14 '05 #3
"dandelion" <so*******@mead own.net> writes:
"Benjamin D. LeMasurier" <ui*****@uidzer 0.org> wrote in message
news:9c******** *************** ***@posting.goo gle.com...
Hey everyone,

Is there a way to "watch" a file for changes? I know I could poll the
file every few seconds and check to see if the buffer has changed but
is there a cleaner way?


Depends on your OS. AFAIK, there is no standard 'C' way to do it. On a POSIX
system, stat() and check atime.


<OT>
mtime, not atime. For details, consult the documentation or an
appropriate newsgroup.
</OT>

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.
Nov 14 '05 #4
"dandelion" <so*******@mead own.net> wrote in message news:<415d286d$ 0$147
Depends on your OS. AFAIK, there is no standard 'C' way to do it. On a POSIX
system, stat() and check atime.

I am in a linux/unix environment. I will give stat() a try

thanks!

Ben
Nov 14 '05 #5

"Keith Thompson" <ks***@mib.or g> wrote in message
news:ln******** ****@nuthaus.mi b.org...
"dandelion" <so*******@mead own.net> writes:
"Benjamin D. LeMasurier" <ui*****@uidzer 0.org> wrote in message
news:9c******** *************** ***@posting.goo gle.com...
Hey everyone,

Is there a way to "watch" a file for changes? I know I could poll the
file every few seconds and check to see if the buffer has changed but
is there a cleaner way?


Depends on your OS. AFAIK, there is no standard 'C' way to do it. On a POSIX system, stat() and check atime.


<OT>
mtime, not atime. For details, consult the documentation or an
appropriate newsgroup.
</OT>


<ot>
Right of course. Errare humanum est.
</ot>
Nov 14 '05 #6

This thread has been closed and replies have been disabled. Please start a new discussion.

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