PTHREAD_CREATE(3P)                   SysV                   PTHREAD_CREATE(3P)



NAME
     pthread_create - Creates a thread

SYNOPSIS
     #include <pthread.h>

     int pthread_create (thread, attr, start_routine, arg)
     pthread_t *thread;
     pthread_attr_t attr;
     void *( *start_routine) (void *arg);
     void *arg;

DESCRIPTION
     The pthread_create function creates a new thread, with attributes
     specified by the attr argument.  If attr is pthread_attr_default, the
     default attributes are used.

     The arguments are as follows:

     thread    Specifies the address in which the ID for the new thread will
               be stored.

     attr      Specifies the address of the attributes object to use in
               creating the new thread.

     start_routine
               Specifies the address of the routine to be executed by the new
               thread.

     arg       Specifies the single argument to be passed to the start_routine
               argument.


     The thread is created executing start_routine, with arg as its sole
     argument.  If start_routine returns, an implicit call to the
     pthread_exit(3P) function is made using the return value of start_routine
     as the exit status.

     Variables accessible to one thread in a process are available to all
     other threads in that process.  Use the pthread_mutex_init(3P) function
     to create a mutex for controlling access to shared data.  Use the
     pthread_keycreate(3P) function to create a key for accessing thread-
     specific data.

     Each thread has its own cancelability state, which determines the
     thread's response to a cancellation request (that is, whether or not the
     thread can be canceled, and when it can be canceled).  There are two
     types of cancelability:  general cancelability (which is set with
     pthread_setcancel(3P) function), and asynchronous cancelability (which is
     set with pthread_setasynccancel(3P) function). They work together to
     determine a thread's cancelability state.  When a thread is created,
     general cancelability is enabled and asynchronous cancelability is
     disabled, which means that the thread can only be canceled at
     cancellation points.

NOTES
     This interface is based on draft 4 of the IEEE P1003.4a standard, and
     will be changed to conform to the final version.

DIAGNOSTICS
     Upon successful completion, the ID of the created thread is stored at

     *thread, and a value of 0 (zero) is returned. Otherwise, no thread is
     created, -1 is returned, and errno is set to indicate the error.

ERRORS
     If the pthread_create function fails, errno may be set to one of the
     following values:

     [EAGAIN]  The system lacks the resources necessary to create another
               thread.

     [EAGAIN]  The new thread cannot be created without exceeding the system-
               imposed limit on the total number of threads allowed for each
               user.

     [ENOMEM]  There is not enough memory to create the thread.  This is not a
               temporary condition.

     [EINVAL]  The value specified by the thread or attr argument is invalid.

SEE ALSO
     fork(2), pthread_exit(3P), pthread_join(3P)