NAME
pthread_create —
create a new thread
LIBRARY
library “libpthread”
SYNOPSIS
#include
<pthread.h>
int
pthread_create(pthread_t
*restrict thread, const
pthread_attr_t *restrict attr,
void *(*start_routine)(void
*), void *restrict
arg);
DESCRIPTION
Thepthread_create()
function is used to create a new thread, with attributes specified by
attr, within a process. If attr is
NULL, the default attributes are used. If the
attributes specified by attr are modified later, the
thread's attributes are not affected. Upon successful completion
pthread_create() will store the ID of the created
thread in the location specified by thread.
The thread is created executing
start_routine with arg as its
sole argument. If the start_routine returns, the
effect is as if there was an implicit call to
pthread_exit()
using the return value of start_routine as the exit
status. Note that the thread in which
main()
was originally invoked differs from this. When it returns from
main(), the effect is as if there was an implicit
call to
exit()
using the return value of main() as the exit
status.
The signal state of the new thread is initialized as:
- The signal mask is inherited from the creating thread.
- The set of signals pending for the new thread is empty.
RETURN VALUES
If successful, the pthread_create()
function will return zero. Otherwise an error number will be returned to
indicate the error.
ERRORS
The pthread_create() function can return
any of the following errors:
- [
ENOMEM] - The system lacked the necessary resources to create another thread.
- [
EAGAIN] - The system-imposed limit on the total number of threads in a process
[PTHREAD_THREADS_MAX]would be exceeded. - [
EAGAIN] - The
RACCT_NTHRlimit would be exceeded; see racct(2). - [
EPERM] - The caller does not have permission to set the scheduling parameters or scheduling policy.
- [
EINVAL] - A value specified by attr is invalid.
- [
EDEADLK] - The CPU set specified by attr would prevent the thread from running on any CPU.
- [
EFAULT] - The stack base specified by attr is invalid, or the kernel was unable to put required initial data on the stack.
SEE ALSO
cpuset_setaffinity(2), fork(2), racct(2), thr_new(2), pthread_attr(3), pthread_cancel(3), pthread_cleanup_pop(3), pthread_cleanup_push(3), pthread_exit(3), pthread_join(3)
STANDARDS
The pthread_create() function conforms to
ISO/IEC 9945-1:1996 (“POSIX.1”).