Re: [PHP] only one at atime

Ahmad Al-Twaijiry wrote:
Hi everyone,

I create a php script that will run every minute (by cronjob) and
update some database tables (php 5, database mysql 5, tables type
innodb)

the problem is that I want this script to run only one at atime (only
one process from this script can run )

for example, if the cronjob start the script and the script takes more
than one minute, then after this one minute the cronjob start another
process from this script, it should exit once it find there is an old
process of it running)

what I do now is that when the script start it will check for a tmp
file (/tmp/script.pid) and if it fine it it will exit.
if the file (/tmp/script.pid) is not exists, it will create it and
start doing the database update
and when the script finish it will remove the file


any better idea ?

Thanks

Nope, typically this is how you solve the problem you mentioned... (just make sure the /tmp directory (or specifically your file are remove when you boot up)
I have seen instances where the machines reboot in the middle of the script and then don't execute for a while because of this *lock file*.
-B
.

Relevant Pages

  • [NEWS] IBM Informix Web DataBlade Local Root by Design
    ... The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com ... that ease development of "intelligent", interactive, Web-enabled database ... person who has access to change the Perl script. ...
    (Securiteam)
  • RE: Need some MySQL query help...
    ... attempting to run the script: ... passed to the database. ... passwd entry to the current database entry. ...
    (perl.dbi.users)
  • Re: script "chaining"
    ... If a task would take too long to run while attached to the browser, the current system writes the data to a database file. ... The daemon checks that file every 10 seconds and executes the task, writing the data back to database. ... If you take the A out of LAMP you can write a php script like a bash script or a perl script and execute it. ...
    (comp.lang.php)
  • Re: script "chaining"
    ... If a task would take too long to run while attached to the browser, the current system writes the data to a database file. ... The daemon checks that file every 10 seconds and executes the task, writing the data back to database. ... If you take the A out of LAMP you can write a php script like a bash script or a perl script and execute it. ...
    (comp.lang.php)
  • Re: Function that returns date of file.
    ... string after the date/time when it is used by itself. ... Is that your entire script? ... I make an IF statement that required the 'equals equals'. ... designed database your job will be all that much harder. ...
    (alt.php)