Description
string
system ( string command [, int return_var])
system() is just like the C version of the
function in that it executes the given
command and outputs the result. If a
variable is provided as the second argument, then the return
status code of the executed command will be written to this
variable.
| Warning |
If you are going to allow data coming from user input to be passed to
this function, then you should be using
escapeshellarg() or
escapeshellcmd() to make sure that users cannot trick
the system into executing arbitrary commands.
|
Note:
If you start a program using this function and want to leave it running
in the background, you have to make sure that the output of that program
is redirected to a file or some other output stream or else PHP will
hang until the execution of the program ends.
The system() call also tries to automatically
flush the web server's output buffer after each line of output if
PHP is running as a server module.
Returns the last line of the command output on success, and FALSE
on failure.
If you need to execute a command and have all the data from the
command passed directly back without any interference, use the
passthru() function.
See also exec(),
passthru(), popen(),
escapeshellcmd(), and the backtick operator.
