PHP4 directly calling C

[Anon]

Hi All,

I am working on a group project at university and have to set up communications through a comm port. The user is interfacing via apache and a PHP script.

I was wondering if, and how, I can call directly C library calls?? - so that I can write a serial port library and have PHP call various functions with different parameters depending on what the user wants.

Thanks in advance,

David Muir
Software Engineering Student
Edinburgh University
Edinburgh, Scotland

[Anon]

You can write your own extensions to PHP.

[frymaster]

i wouldn\'t suggest using a series of modules for php. The zend api really restricts using existing C code. Instead, I\'d write a wrapper C program that takes the function you want to call and its args and calls said function sending output to stdout. Then in php, I\'d call the wrapper program with popen() and read the returns off the pointer provided. viz

wrapper.c

#include \"my_fancy_lib.h\"

int main(int arc, char *argv[])
{
// do some seteuid here since apache runs
// under a limited account

// do a switch here on argv[1] which
// is your library call. run the call with
// argv[2] to (argv[argc-2]) or similar.

//exit

}

compile to taste. in php

$my_arg = \"foo\";
$my_arg2 = \"bar\"; // this calls for an array really

popen (\"a.out $my_arg $my_arg2\", $result);

// now open $result pointer and enjoy

that\'s completely off the top of my head... fair warning.