problem with mutltiple fork() Post: 302605479

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wait.h

wait.h(3HEAD)                                                         Headers                                                        wait.h(3HEAD)

NAME

       wait.h, wait - wait status

SYNOPSIS

       #include <sys/wait.h>

DESCRIPTION

       When  a  process waits for status from its children using either the wait(3C) or waitpid(3C) function, the status returned can be evaluated
       with the following macros, defined in <sys/wait.h>. These macros evaluate to integral expressions. The stat argument to these macros is the
       integer value returned from wait() or waitpid().

       WCOREDUMP(stat)                 If the value of WIFSIGNALED (stat) is non-zero, this macro evaluates to a non-zero value if a core image of
                                       the terminated child was created.

       WEXITSTATUS(stat)               If the value of  WIFEXITED(stat) is non-zero, this macro evaluates to the exit code that the child  process
                                       passed to  _exit() (see exit(2)) or exit(3C), or the value that the child process returned from main.

       WIFCONTINUED(stat)              Evaluates to a non-zero value if status was returned for a child process that has continued.

       WIFEXITED(stat)                 Evaluates to a non-zero value if status was returned for a child process that terminated normally.

       WIFSIGNALED(stat)               Evaluates to a non-zero value if status was returned for a child process that terminated due to the receipt
                                       of a signal.

       WIFSTOPPED(stat)                Evaluates to a non-zero value if status was returned for a child process that is currently stopped.

       WSTOPSIG(stat)                  If the value of WIFSTOPPED(stat) is non-zero, this macro evaluates to the number of the signal that  caused
                                       the child process to stop.

       WTERMSIG(stat)                  If  the  value  of   WIFSIGNALED(stat)  is  non-zero, this macro evaluates to the number of the signal that
                                       caused the termination of the child process.

       The <sys/wait.h> header defines the symbolic constants listed below for use with waitpid(3C).

       WNOHANG         Do not hang if no status is available; return immediately.

       WUNTRACED       Report status of stopped child process.

       The symbolic constants listed below are defined as possible values for the options argument to waitid(2).

       WEXITED         Wait for processes that have exited.

       WSTOPPED        Status is returned for any child that has stopped upon receipt of a signal.

       WCONTINUED      Status is returned for any child that was stopped and has been continued.

       WNOHANG         Return immediately if there are no children to wait for.

       WNOWAIT         Keep the process whose status is returned in infop in a waitable state.

       The type idtype_t is defined as an enumeration type whose possible values include the following:

       P_ALL
       P_PID
       P_PGID

       The id_t and pid_t types are defined as described in <sys/types.h>.

       The siginfo_t type is defined as described in <signal.h>.

       The rusage structure is defined as described in <sys/resource.h>.

       Inclusion of the <sys/wait.h> header can also make visible all symbols from <signal.h> and <sys/resource.h>.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       +-----------------------------+-----------------------------+
       |Interface Stability          |Standard                     |
       +-----------------------------+-----------------------------+

SEE ALSO

       exit(2), waitid(2), exit(3C), wait(3C), waitpid(3C),attributes(5), standards(5)

SunOS 5.10                                                          10 Sep 2004                                                      wait.h(3HEAD)