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IDProjectCategoryView StatusDate SubmittedLast Update
00009591003.1(2008)/Issue 7Base Definitions and Headerspublic2015-06-18 11:102015-07-30 15:04
Reporterjoerg Assigned Toajosey  
PrioritynormalSeverityEditorialTypeClarification Requested
Status ClosedResolutionWithdrawn 
NameJörg Schilling
Organization
User Reference
SectionHeaders
Page Number335-336
Line Number11179, 11185, 11218-11223
Interp Status---
Final Accepted Text
Summary0000959: struct siginfo member si_pid is marked "CX" but is mandatory for the non-CX waitid()
DescriptionIn order to make waitid() usable, the siginfo_t members

si_pid
si_code
si_status

need to be mandatory and siginfo_t as a whole needs to be mandatory as well.
Desired ActionRemove the "CX" marker for siginfo_t on line 11179 and
remove the "CX" marker for si_pid on line 11185 and change

          Sending process ID.

to

          Sending process ID or child pid for waitid().

Remove the "CX" marker for the constants CLD_EXITED .. CLD_CONTINUED
at line 11218..11223.

In order to make waitid() usable at shell level, it may be needed to
require CLD_EXITED .. CLD_CONTINUED to use the range 1..6.
TagsNo tags attached.

Relationships

related to 0000690 Closed 1003.1(2013)/Issue7+TC1 clarify behavior when calling waitpid with SA_NOCLDWAIT 

Activities

joerg

2015-06-18 11:11

reporter   bugnote:0002715

Last edited: 2015-06-18 11:11

 Here is a test program that allows to check whether a implementation
conforms to the standard:

#include <stdlib.h>
#include <unistd.h>
#include <sys/wait.h>
#include <stdio.h>
/*
 * Non-standard compliant platforms may need
 * #include <signal.h> or something similar
 * in addition to the include files above.
 */

int
main()
{
        siginfo_t si;
        pid_t pid;
        int ret;

        if ((pid = fork()) < 0)
                exit(1);
        if (pid == 0) {
                _exit(1234567890);
        }
        ret = waitid(P_PID, pid, &si, WEXITED);
        printf("ret: %d si_pid: %ld si_status: %d si_code: %d\n",
                ret,
                (long) si.si_pid, si.si_status, si.si_code);
        if (pid != si.si_pid)
                printf("si_pid in struct siginfo should be %ld but is %ld\n",
                        (long) pid, (long) si.si_pid);
        if (si.si_status != 1234567890)
                printf("si_status in struct signinfo should be %d (0x%x) but is %d (0x%x)\n",
                        1234567890, 1234567890, si.si_status, si.si_status);
        if (CLD_EXITED != 1)
                printf("CLD_EXITED is %d on this platform\n", CLD_EXITED);
        return (0);
}

geoffclare

2015-06-18 11:32

manager   bugnote:0002716

This bug report seems to be the result of a misunderstanding of what the CX margin code means. Hint: it does not indicate that something is optional!

joerg

2015-06-18 11:46

reporter   bugnote:0002717

So do you believe that this is just an extension to ISO C but
mandatory for POSIX?

The interesting thing here is that e.g. Mac OS X returns si_pid == 0
for waitid() and does not seem to implement a useable waitid()
interface.

eblake

2015-06-18 18:36

manager   bugnote:0002722

See XBD 1.7.1 line 182. Something marked CX is mandatory in POSIX, and merely marked as a convenience to show that it is an extension to C99.

rhansen

2015-07-10 21:48

manager   bugnote:0002753

Last edited: 2015-07-10 21:48

 > So do you believe that this is just an extension to ISO C but
> mandatory for POSIX?

Yes. Key quotes from the section Eric mentioned (XBD 1.7.1, definition of CX shading):
  • "Application developers may make use of an extension as it is supported on all POSIX.1-2008-conforming systems." (page 7 lines 183-184)

  • "The markings are for information only." (page 7 line 189)
So the CX shading mismatch is not a bug.

Note that 0000690 changed some shading; I don't recall whether there's any overlap with this bug report.

Issue History

Date Modified Username Field Change
2015-06-18 11:10 joerg New Issue
2015-06-18 11:10 joerg Status New => Under Review
2015-06-18 11:10 joerg Assigned To => ajosey
2015-06-18 11:10 joerg Name => Jörg Schilling
2015-06-18 11:10 joerg Section => Headers
2015-06-18 11:10 joerg Page Number => 335-336
2015-06-18 11:10 joerg Line Number => 11179, 11185, 11218-11223
2015-06-18 11:11 joerg Note Added: 0002715
2015-06-18 11:11 joerg Note Edited: 0002715
2015-06-18 11:32 geoffclare Note Added: 0002716
2015-06-18 11:46 joerg Note Added: 0002717
2015-06-18 18:36 eblake Note Added: 0002722
2015-07-10 21:39 rhansen Relationship added related to 0000690
2015-07-10 21:48 rhansen Note Added: 0002753
2015-07-10 21:48 rhansen Note Edited: 0002753
2015-07-30 15:04 Don Cragun Interp Status => ---
2015-07-30 15:04 Don Cragun Status Under Review => Closed
2015-07-30 15:04 Don Cragun Resolution Open => Withdrawn