PHP Extension: call_user_function from a pthread returns error -

i working on php extension. php extension should make use of multithreading via pthreads. inside thread function in php userspace should called via call_user_function. php configured --enable-maintainer-zts config option.

i have written code calls php function in user space works expected. see following code snippets minimal working example:

extension code (in c)

php_function(hello_world) {     startworker();     return_null(); }  void *startworker() {      static zval retval;      zval function_name;     init_zval(function_name);     zval_string(&function_name, "hello", 1);      tsrmls_fetch();      if (call_user_function(cg(function_table), null, &function_name, &retval, 0, null tsrmls_cc) == success) {         printf("successfully called function\n");     } else {         printf("calling user function returned error\n");     }      zval_dtor(&function_name); } 

php code:

<?php  function hello() {         echo "php hello() called\n"; } hello_world(); 

if call php code, returns following output - expected.

php hello() called called function 

but want call php function new thread. modify extension code follows:

php_function(hello_world) {     pthread_t thread;     pthread_create( &thread, null, &startworker, null);     pthread_join(thread, null);     return_null(); } 

but now, of sudden, calling php code results in following output:

calling user function returned error 

i track down source of error following if statement in zend_call_function, have no idea why eg(active) false @ point how can prevent this:

if (!eg(active)) {     return failure; /* executor inactive */ } 

so questions are:

• is possible call php userspace functions inside threads?
• if so, why call_user_function return error?
• what eg(active) mean? how can make evaluate true inside pthread?

any hints on highly appreciated.