Re: [PHP] File locking in PHP???
* Thus wrote Scott Fletcher:
> Nah! I'll settle for a simplier one... file_exists() by checking to see
> if the file exist then spit out the error message. Meaning the file is in
> use...
Don't use file_exists() for that, it will fail miserable with
racing conditions. a better more portable way would be to use
mkdir():
if (mkdir('mylockdir', 0755) ) {
// we've obtained a lock
// do stuff
// and unlock it
rmdir('mylockdir');
} else {
// unable to obtain lock
}
Curt
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Re: [PHP] File locking in PHP???
Nah! I'll settle for a simplier one... file_exists() by checking to see if the file exist then spit out the error message. Meaning the file is in use... FletchSOD "Matt M." <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > > Hi! I saw the php function flock(), since I never used it before so I > > thought I would ask you folks a couple of questions. > > did you read all of the user comments on http://us2.php.net/flock > > There is a bunch of good info in there -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] File locking in PHP???
Yea, read that, very good info there. Alright, I'll make one from scratch and do some testing to find what need to be add/change/remove to make it more a rock solid script. Boy, it remind me of Perl. Thanks, FletchSOD "Matt M." <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > > Hi! I saw the php function flock(), since I never used it before so I > > thought I would ask you folks a couple of questions. > > did you read all of the user comments on http://us2.php.net/flock > > There is a bunch of good info in there -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] File locking in PHP???
> Hi! I saw the php function flock(), since I never used it before so I > thought I would ask you folks a couple of questions. did you read all of the user comments on http://us2.php.net/flock There is a bunch of good info in there -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
[PHP] File locking in PHP???
Hi! I saw the php function flock(), since I never used it before so I thought I would ask you folks a couple of questions. 1) Is this function good or is there a better function somewhere that I'm not aware of? 2) If the flock() activated the file lock then is it possible that I manually unlock the file? Like chmod or something through the Linux console for example. 3) good example of script just in case.. Thanks, FletchSOD -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] File Locking in PHP.
On Tue, 20 Feb 2001 08:50, Matthew Toledo wrote: > Hello, I am just starting to use PHP. I have been using PERL for quite > some time. I was wondering if there is any specific FILE LOCKING I > need to implement to keep more than one person from altering a text > file at the same time. > > For instance, in PERL, you use the flock command to set up an advisory > file lock. Lets say that if I have a web page with a text based > database, and more than one person wants to write to the file at the > same time. In perl, if you use flock(FILE, 2). This causes person A > to wait while person B writes to the file. flock(FILE, 8) unlocks the > file. Then person A is allowed to write to the file. > > Does the perl equivalent of flock happen automatically in PHP? > > If not, how do you lock a file? > > Is it an advisory lock, or will it cause an error if two people try to > access the same file at the same time for the same purpose (writing). > > Thanks, The flock() function in PHP seems to do pretty much what you are looking for - it allows setting a shared or exclusive lock and you can control blocking while locking (at least according to the manual!) -- David Robley| WEBMASTER & Mail List Admin RESEARCH CENTRE FOR INJURY STUDIES | http://www.nisu.flinders.edu.au/ AusEinet| http://auseinet.flinders.edu.au/ Flinders University, ADELAIDE, SOUTH AUSTRALIA -- PHP General Mailing List (http://www.php.net/) To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED]
[PHP] File Locking in PHP.
Hello, I am just starting to use PHP. I have been using PERL for quite some time. I was wondering if there is any specific FILE LOCKING I need to implement to keep more than one person from altering a text file at the same time. For instance, in PERL, you use the flock command to set up an advisory file lock. Lets say that if I have a web page with a text based database, and more than one person wants to write to the file at the same time. In perl, if you use flock(FILE, 2). This causes person A to wait while person B writes to the file. flock(FILE, 8) unlocks the file. Then person A is allowed to write to the file. Does the perl equivalent of flock happen automatically in PHP? If not, how do you lock a file? Is it an advisory lock, or will it cause an error if two people try to access the same file at the same time for the same purpose (writing). Thanks, === Matthew Toledo FrogNet Design & Domain Management [EMAIL PROTECTED] -- PHP Language Mailing List (http://www.php.net/) To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED] -- PHP General Mailing List (http://www.php.net/) To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED]
