c++.windows.32-bits - [possible bug] cwait undefined?
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Anuj Goyal
(23/23)
Jul 17 2004
#include
- Walter (4/27) Jul 17 2004 spawnlp returns the exit status directly, not the process id. It doesn't
- Anuj Goyal (6/45) Jul 17 2004 if there is no way to wait, does the parent process block until the spaw...
- Anuj Goyal (15/64) Jul 17 2004 nevermind, I guess that can be controlled by these modes:
- Anuj Goyal (3/52) Jul 17 2004 sorry again, I should have looked here in the frist place:
#include <stdio.h> #include <process.h> int main() { int pid; int tstat = 0xdeadbeef; printf("Running ls with spawnlp\n"); pid = _spawnlp( _P_NOWAIT, "ls", "ls", NULL ); // Suspend our execution until the child has terminated. // obtain termination code upon completion. cwait(&tstat, pid, WAIT_CHILD); printf("\nChild process %d terminated with code 0x%x.\n", pid, tstat); exit(0); } this is the error I get: D:\ccache-2.3>dmc -WA anuj.c link anuj,,,user32+kernel32/noi; OPTLINK (R) for Win32 Release 7.50B1 Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved anuj.obj(anuj) Error 42: Symbol Undefined _cwait --- errorlevel 1 However, cwait is defined in c:\dm\include\process.h (line 110)
Jul 17 2004
spawnlp returns the exit status directly, not the process id. It doesn't work like unix. "Anuj Goyal" <Anuj_member pathlink.com> wrote in message news:cdblcb$1ego$1 digitaldaemon.com...#include <stdio.h> #include <process.h> int main() { int pid; int tstat = 0xdeadbeef; printf("Running ls with spawnlp\n"); pid = _spawnlp( _P_NOWAIT, "ls", "ls", NULL ); // Suspend our execution until the child has terminated. // obtain termination code upon completion. cwait(&tstat, pid, WAIT_CHILD); printf("\nChild process %d terminated with code 0x%x.\n", pid, tstat); exit(0); } this is the error I get: D:\ccache-2.3>dmc -WA anuj.c link anuj,,,user32+kernel32/noi; OPTLINK (R) for Win32 Release 7.50B1 Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved anuj.obj(anuj) Error 42: Symbol Undefined _cwait --- errorlevel 1 However, cwait is defined in c:\dm\include\process.h (line 110)
Jul 17 2004
if there is no way to wait, does the parent process block until the spawnlp'd process completes? I can test this but thought I would ask the man himself ;) I got the code from the M$ site: Appendix G http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnucmg/html/UCMGch09.asp In article <cdcgus$1q1s$1 digitaldaemon.com>, Walter says...spawnlp returns the exit status directly, not the process id. It doesn't work like unix. "Anuj Goyal" <Anuj_member pathlink.com> wrote in message news:cdblcb$1ego$1 digitaldaemon.com...#include <stdio.h> #include <process.h> int main() { int pid; int tstat = 0xdeadbeef; printf("Running ls with spawnlp\n"); pid = _spawnlp( _P_NOWAIT, "ls", "ls", NULL ); // Suspend our execution until the child has terminated. // obtain termination code upon completion. cwait(&tstat, pid, WAIT_CHILD); printf("\nChild process %d terminated with code 0x%x.\n", pid, tstat); exit(0); } this is the error I get: D:\ccache-2.3>dmc -WA anuj.c link anuj,,,user32+kernel32/noi; OPTLINK (R) for Win32 Release 7.50B1 Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved anuj.obj(anuj) Error 42: Symbol Undefined _cwait --- errorlevel 1 However, cwait is defined in c:\dm\include\process.h (line 110)
Jul 17 2004
Anuj Goyal <Anuj_member pathlink.com> nevermind, I guess that can be controlled by these modes: _P_OVERLAY Overlays calling process with new process, destroying the calling process (same effect as _exec calls). _P_WAIT Suspends calling thread until execution of new process is complete (synchronous _spawn). _P_NOWAIT or _P_NOWAITO Continues to execute calling process concurrently with new process (asynchronous _spawn). _P_DETACH Continues to execute the calling process; new process is run in the background with no access to the console or keyboard. Calls to _cwait against the new process will fail (asynchronous _spawn). In article <cdcmm9$1s10$1 digitaldaemon.com>, Anuj Goyal says...if there is no way to wait, does the parent process block until the spawnlp'd process completes? I can test this but thought I would ask the man himself ;) I got the code from the M$ site: Appendix G http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnucmg/html/UCMGch09.asp In article <cdcgus$1q1s$1 digitaldaemon.com>, Walter says...spawnlp returns the exit status directly, not the process id. It doesn't work like unix. "Anuj Goyal" <Anuj_member pathlink.com> wrote in message news:cdblcb$1ego$1 digitaldaemon.com...#include <stdio.h> #include <process.h> int main() { int pid; int tstat = 0xdeadbeef; printf("Running ls with spawnlp\n"); pid = _spawnlp( _P_NOWAIT, "ls", "ls", NULL ); // Suspend our execution until the child has terminated. // obtain termination code upon completion. cwait(&tstat, pid, WAIT_CHILD); printf("\nChild process %d terminated with code 0x%x.\n", pid, tstat); exit(0); } this is the error I get: D:\ccache-2.3>dmc -WA anuj.c link anuj,,,user32+kernel32/noi; OPTLINK (R) for Win32 Release 7.50B1 Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved anuj.obj(anuj) Error 42: Symbol Undefined _cwait --- errorlevel 1 However, cwait is defined in c:\dm\include\process.h (line 110)
Jul 17 2004
sorry again, I should have looked here in the frist place: http://www.digitalmars.com/rtl/process.html In article <cdcmm9$1s10$1 digitaldaemon.com>, Anuj Goyal says...if there is no way to wait, does the parent process block until the spawnlp'd process completes? I can test this but thought I would ask the man himself ;) I got the code from the M$ site: Appendix G http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnucmg/html/UCMGch09.asp In article <cdcgus$1q1s$1 digitaldaemon.com>, Walter says...spawnlp returns the exit status directly, not the process id. It doesn't work like unix. "Anuj Goyal" <Anuj_member pathlink.com> wrote in message news:cdblcb$1ego$1 digitaldaemon.com...#include <stdio.h> #include <process.h> int main() { int pid; int tstat = 0xdeadbeef; printf("Running ls with spawnlp\n"); pid = _spawnlp( _P_NOWAIT, "ls", "ls", NULL ); // Suspend our execution until the child has terminated. // obtain termination code upon completion. cwait(&tstat, pid, WAIT_CHILD); printf("\nChild process %d terminated with code 0x%x.\n", pid, tstat); exit(0); } this is the error I get: D:\ccache-2.3>dmc -WA anuj.c link anuj,,,user32+kernel32/noi; OPTLINK (R) for Win32 Release 7.50B1 Copyright (C) Digital Mars 1989 - 2001 All Rights Reserved anuj.obj(anuj) Error 42: Symbol Undefined _cwait --- errorlevel 1 However, cwait is defined in c:\dm\include\process.h (line 110)
Jul 17 2004