fwrite - Php Lock files when writte -

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i testing code using little database in txt files. important problem have found is: when users write @ same time 1 file. solve using flock. os of computer windows xampp installed (comment because understand flocks works fine on linux no windows) need test on linux server.

actually have tested code loading same script in 20 windows @ same time. firsts results works fine, after test database file appears empty.

my code :

$file_db=file("test.db"); $fd=fopen("".$db_name."","w");  if (flock($fd, lock_ex))      {      ftruncate($fd,0);      ($i=0;$i<sizeof($file_db);$i++)         {         fputs($fd,"$file_db[$i]"."\n");         }     fflush($fd);      flock($fd, lock_un);     fclose($fd);     } else     {     print "db busy";     }

how it's possible script deletes database file content. proper way: use flock fixing of existing code or use other alternative technique of flock?

i have re-wrote script using @lolka_bolka's answer , works. in answer question, file $db_name empty if file test.db empty.


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