[PHP] about lock some codes.
Hello: I have a question now.the code is: $ftemp = fopen($fdoc_tmp/temp_proxy, 'w'); fwrite($ftemp, $content); fclose($ftemp); exec(/usr/local/bin/gdnsproxy -a -f $fdoc_tmp/temp_proxy 1$fdoc_tmp/dout 2$fdoc_tmp/derr, $data, $ex_result); echo ret=.$ex_result; As you see, If a process run these,this is right.But two processes run this codes. the order maybe is: 1.process 1 create the temp_proxy1 2.process 2 create the temp_proxy2 3.process 1 exec temp_proxy2 4.process 2 exec temp_proxy2 The temp_proxy1 can't exec. So,I want to know how to solve it. Thank you.
Re: [PHP] about lock some codes.
On 27-09-2012 11:31, lx wrote: Hello: I have a question now.the code is: $ftemp = fopen($fdoc_tmp/temp_proxy, 'w'); fwrite($ftemp, $content); fclose($ftemp); exec(/usr/local/bin/gdnsproxy -a -f $fdoc_tmp/temp_proxy 1$fdoc_tmp/dout 2$fdoc_tmp/derr, $data, $ex_result); echo ret=.$ex_result; As you see, If a process run these,this is right.But two processes run this codes. the order maybe is: 1.process 1 create the temp_proxy1 2.process 2 create the temp_proxy2 3.process 1 exec temp_proxy2 4.process 2 exec temp_proxy2 The temp_proxy1 can't exec. So,I want to know how to solve it. Thank you. Well, there are basically 2 ways: 1. introduce locking; you can lock the file and have the other script check if the file is locked. If so have it usleep() and check again. 2. If you can run gdnsproxy in parallel, you could instead change the script to make $fdoc_tmp/temp_proxy unique for that script. So instead of just writing, you first check if the file exists, if so, create a file with a different (non-existent) name and then try again. Otherwise, use the first name. Then pass the 'unique' name to gdnsproxy. -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] about lock some codes.
On 9/27/2012 7:05 AM, Maciek Sokolewicz wrote: On 27-09-2012 11:31, lx wrote: Hello: I have a question now.the code is: $ftemp = fopen($fdoc_tmp/temp_proxy, 'w'); fwrite($ftemp, $content); fclose($ftemp); exec(/usr/local/bin/gdnsproxy -a -f $fdoc_tmp/temp_proxy 1$fdoc_tmp/dout 2$fdoc_tmp/derr, $data, $ex_result); echo ret=.$ex_result; As you see, If a process run these,this is right.But two processes run this codes. the order maybe is: 1.process 1 create the temp_proxy1 2.process 2 create the temp_proxy2 3.process 1 exec temp_proxy2 4.process 2 exec temp_proxy2 The temp_proxy1 can't exec. So,I want to know how to solve it. Thank you. Well, there are basically 2 ways: 1. introduce locking; you can lock the file and have the other script check if the file is locked. If so have it usleep() and check again. 2. If you can run gdnsproxy in parallel, you could instead change the script to make $fdoc_tmp/temp_proxy unique for that script. So instead of just writing, you first check if the file exists, if so, create a file with a different (non-existent) name and then try again. Otherwise, use the first name. Then pass the 'unique' name to gdnsproxy. Even simpler - use the 'tempnam' or 'tmpfile' functions to always have a unique name and avoid having to check for an existing file. Amazing what the php Manual has in it... -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] about lock some codes.
On 27-09-2012 15:13, Jim Giner wrote: Even simpler - use the 'tempnam' or 'tmpfile' functions to always have a unique name and avoid having to check for an existing file. Amazing what the php Manual has in it... Good find, I completely forgot about the existence of those functions ;) It's been a long time since I've had to meddle with unique filenames -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
