Re: exec and system do not work

Ethan Rosenberg, PhD /Pres/CEO/ *Hygeia Biomedical Research, Inc* 2 Cameo Ridge Road Monsey, NY 10952 T: 845 352-3908 F: 845 352-7566 erosenberg@hygeiabiomedical.com On 08/26/2013 07:33 PM, David Robley wrote:

Ethan Rosenberg wrote:

On 08/26/2013 11:36 AM, marco@behnke.biz wrote:

Tamara Temple <tamouse.lists@gmail.com> hat am 26. August 2013 um 08:33 geschrieben: On Aug 25, 2013, at 10:41 PM, Ethan Rosenberg <erosenberg@hygeiabiomedical.com> wrote:

Dear List - I'm lost on this one - This works - $out = system("ls -l ",$retvals); printf("%s", $out); This does - echo exec("ls -l");

Please show the output of the directory listing. Please us "ls -la"

This does not - if( !file_exists("/var/www/orders.txt")); {

     $out = system("touch /var/www/orders.txt", $ret);

Maybe you don't have write permissions on the folder?

     $out2 = system("chmod 766 /var/www/orders.txt", $ret);
     echo 'file2<br />';
     echo file_exists("/var/www/orders.txt");

} and this does not - if( !file_exists("/var/www/orders.txt")); {

     exec("touch /var/www/orders.txt");
     exec("chmod 766 /var/www/orders.txt");
     echo 'file2<br />';
     echo file_exists("/var/www/orders.txt");

} Ethan

When you say "does not work", can you show what is actually not working? I believe the exec and system functions are likely working just fine, but that the commands you've passed to them may not be.

-- Marco Behnke Dipl. Informatiker (FH), SAE Audio Engineer Diploma Zend Certified Engineer PHP 5.3 Tel.: 0174 / 9722336 e-Mail: marco@behnke.biz Softwaretechnik Behnke Heinrich-Heine-Str. 7D 21218 Seevetal http://www.behnke.biz

Tamara -

Please show the output of the directory listing. Please us "ls -la"

echo exec('ls -la orders.txt'); -rw-rw-rw- 1 ethan ethan 43 Aug 25 23:50 orders.txt Maybe you don't have write permissions on the folder? If I perform the touch and chmod from the command line, everything works.

When you say "does not work", can you show what is actually not

working? I

believe the exec and system functions are likely working just fine,

but that

the commands you've passed to them may not be.

Here are my commands. if( !file_exists("/var/www/orders.txt")); { echo system("touch /var/www/orders.txt", $ret); echo system("chmod 766 /var/www/orders.txt", $ret); echo 'file2<br />'; echo file_exists("/var/www/orders.txt"); } If I now try a ls from the command line, the return is cannot access /var/www/orders.txt: No such file or directory The ls -la works because the file was created from the command line. TIA Ethan

Note that touch and chmod don't return any output, so echoing the result of a system call for those commands will give an empty string. You should be checking the values of $ret for each execution of system to see whether the command was successful or not - the return status of the executed command will be written to this variable. I'd guess that touch is returning 13 - permission denied. if( !file_exists("/var/www/orders.txt")) { system("touch /var/www/orders.txt", $ret1); echo 'touch returned '.$ret1.'<br> /'; system("chmod 766 /var/www/orders.txt", $ret2); echo 'chmod returned ' .$ret2.'<br> /'; echo 'file2<br />'; echo file_exists("/var/www/orders.txt"); } Check the permissions for directory /var/www; you'll probably find it is writable by the user you log on as, but not by the user that apache/php runs as, which is often www - a user with limited privileges. As other(s) have pointed out, there are php functions to do what you want without introducing the possible insecurities involved with system et al.

David - touch returned 1 /chmod returned 1 rosenberg:/var/www# ls orders.txt ls: cannot access orders.txt: No such file or directory rosenberg:/var# ls -ld www drwxr-xr-x 37 ethan ethan 20480 Aug 26 20:15 www TIA Ethan