0p:sys wait.h

From Linux Man Pages

Jump to: navigation, search
      sys/wait.h - declarations for waiting
      
      #include <sys/wait.h>

Contents

DESCRIPTION

      The <sys/wait.h> header shall define the following symbolic constants for use with waitpid():
 
      WNOHANG
             Do not hang if no status is available; return immediately.
 
      WUNTRACED
             Report status of stopped child process.
 
      The <sys/wait.h> header shall define the following macros for analysis of process status values:
 
      WEXITSTATUS
             Return exit status.
 
      WIFCONTINUED
             True if child has been continued.
 
      WIFEXITED
             True if child exited normally.
 
      WIFSIGNALED
             True if child exited due to uncaught signal.
 
      WIFSTOPPED
             True if child is currently stopped.
 
      WSTOPSIG
             Return signal number that caused process to stop.
 
      WTERMSIG
             Return signal number that caused process to terminate.
 
      The following symbolic constants shall be defined as possible values for the options argument to waitid():
 
      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 shall be defined as an enumeration type whose possible values shall include at least the fol-
      lowing: P_ALL P_PID P_PGID
 
      The id_t and pid_t types shall be defined as described in <sys/types.h> .
 
      The siginfo_t type shall be defined as described in <signal.h> .
 
      The rusage structure shall be defined as described in <sys/resource.h> .
 
      Inclusion of the <sys/wait.h> header may also make visible all symbols from <signal.h> and <sys/resource.h>.
 
      The following shall be declared as functions and may also be defined as macros. Function prototypes shall be pro-
      vided.
 
             pid_t  wait(int *);
 
             int    waitid(idtype_t, id_t, siginfo_t *, int);
 
             pid_t  waitpid(pid_t, int *, int);
 
      The following sections are informative.

APPLICATION USAGE

      None.

RATIONALE

      None.

FUTURE DIRECTIONS

      None.

RELATED

      <signal.h>  ,  <sys/resource.h>  ,  <sys/types.h> , the System Interfaces volume of IEEE Std 1003.1-2001, wait(),
      waitid()

COPYRIGHT

      Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003  Edition,  Stan-
      dard  for  Information  Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifica-
      tions Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open
      Group.  In  the  event of any discrepancy between this version and the original IEEE and The Open Group Standard,
      the original IEEE and The Open Group Standard is the referee document. The  original  Standard  can  be  obtained
      online at http://www.opengroup.org/unix/online.html .


IEEE/The Open Group 2003 <sys/wait.h>(P)

CATEGORY

Personal tools