performance - how to make a php automation background script for Windows and Unix? -

i have script creates thumbnails of larger images , works fine, problem is placed @ beginning of page both images viewed , understanding run every time visits page. doesn't seem performant.

i rather script have own page , somehow detected when more large images had been added directory scans , go work then.

how go setting or improving in someway?

found this, not sure how works. $cmd:

  /*i combined several efforts in topic 1 function:  execute $cmd in background (no cmd window)  without php waiting finish, on both windows , unix.*/     function execinbackground($cmd) {          if (substr(php_uname(), 0, 7) == "windows"){              pclose(popen("start /b ". $cmd, "r"));           }          else {              exec($cmd . " > /dev/null &");            }      }  

time base creation : perhaps (if have shell access), can create "cron job" :

in ''/etc/crond.d/'' create file :

0 6-18 * * *    root    /path/to/your/script.php >> /dev/null 2>&1 

it execute every hour 6.00 18.00.

see : http://en.wikipedia.org/wiki/cron more details.

automatic creation : if have "upload procedure", put "thumbnail generator" after uploading.

hook creation : indeed, depend of procedure use add new images in directory.

perhaps, can make hook execute script after updating dir.

but think first solution based on time (cron) easy implement.