PXFWAIT(3F) Last changed: 1-6-98
NAME
PXFWAIT, PXFWAITPID - Obtains information about a calling process'
child process
SYNOPSIS
SUBROUTINE PXFWAIT (istat, iretpid, ierror)
INTEGER istat, iretpid, ierror
SUBROUTINE PXFWAITPID (ipid, istat, ioptions, iretpid, ierror)
INTEGER ipid, istat, ioptions, iretpid, ierror
IMPLEMENTATION
UNICOS, UNICOS/mk, and IRIX systems
DESCRIPTION
On IRIX systems, this routine is in libfortran.so which is linked by
default when compiling programs with the MIPSpro 7 Fortran 90 compiler
or when compiling programs with the -craylibs option to the MIPSpro
7.2 F77 compiler.
The PXFWAIT routine uses the wait(2) system call to obtain information
about one of the calling process's child processes.
The PXFWAITPID routine uses the waitpid(2) system call to obtain
information about one of the calling process's child processes.
When using the CF90 compiler or MIPSpro 7 Fortran 90 compiler on
UNICOS, UNICOS/mk, or IRIX systems, all arguments must be of default
kind unless documented otherwise. On UNICOS and UNICOS/mk, default
kind is KIND=8 for integer, real, complex, and logical arguments; on
IRIX, the default kind is KIND=4.
The following is a list of arguments for this routine:
ipid An input integer variable containing the child process ID
for which information is requested.
* If ipid is equal to -1, status is requested for any child
process; PXFWAITPID is then equivalent to PXFWAIT.
* If ipid is greater than 0, it specifies the process ID of
a single child process for which status is requested.
* If ipid is equal to 0, status is requested for any child
process with a process group ID that is equal to that of
the calling process.
* If ipid is less than -1, status is requested for any child
process with a process group ID that is equal to the
absolute value of ipid.
istat An output integer variable for the status information.
ioptions An input integer variable constructed from an inclusive OR
of zero or more of the following options:
WNOHANG The waitpid system call does not suspend
execution of the calling process if status is
not immediately available for one of the calling
processes specified by pid.
WUNTRACED If job control is supported, the status of any
child processes specified by pid that are
stopped, and with a status that has not yet been
reported since they stopped, are also reported
to the requesting process.
UNICOS and UNICOS/mk systems only:
WMTWAIT Waits for the children of any member of the
multitasking group. In UNICOS 9.0 this is the
default behavior for both wait and waitpid. The
flag is still provided for source compatibility.
To get the previous behavior, see the
description of the WLWPWAIT flag.
WLWPWAIT Waits only for the immediate children of the
calling light-weight process (LWP). This flag
is not recommended for general use.
iretpid An output integer variable for the child process ID.
ierror An output integer variable that contains zero if the routine
was successful or nonzero if the routine was not successful.
Any of the following error values may be returned:
ECHILD PXFWAIT: If the calling process has no existing unwaited-for
child processes.
PXFWAITPID: The process or process group specified by ipid
does not exist or is not a child of the calling process.
EINTR If receipt of a signal other than the death-of-a-child-
process signal.
EINVAL The value of the ioptions argument is not valid.
EXAMPLES
PXFWAIT example:
program pxftest
integer istat, iretpid, ipid, ierror, i, j
CALL PXFFORK(ipid,ierror)
if (ierror .ne. 0) then
print *,'FAILED: PXFFORK call failed with error = ',ierror
else
if (ipid .eq. 0) then
j = 0
do i=1,100000
j = j + i
enddo
stop
else
CALL PXFWAIT(istat,iretpid,ierror)
if (ierror .eq. 0) then
print *,'PASSED: PXFWAIT normal test'
else
print *,'FAILED: PXFWAIT call with error = ',ierror
endif
endif
endif
end
PXFWAITPID example:
program pxftest
integer istat, iretpid, ipid, ierror, i, j, ioptions
CALL PXFFORK(ipid,ierror)
if (ierror .ne. 0) then
print *,'FAILED: PXFFORK call failed with error = ',ierror
else
if (ipid .eq. 0) then
j = 0
do i=1,100000
j = j + i
enddo
stop
else
ioptions = 0
CALL PXFWAITPID(ipid,istat,ioptions,iretpid,ierror)
if (ierror .eq. 0) then
print *,'PASSED: PXFWAITPID normal test'
else
print *,'FAILED: PXFWAITPID call with error = ',ierror
endif
endif
endif
end
SEE ALSOwait(2), waitpid(2)
Application Programmer's Library Reference Manual, publication SR-
2165, for the printed version of this man page.
