setgroupspid()

Updated: May 06, 2022

Set supplementary group IDs for a child process

Synopsis:

#include <unistd.h>

int setgroupspid( int gidsetsize,
                  const gid_t *grouplist,
                  pid_t pid );

Arguments:

gidsetsize
The number of entries in the grouplist array. This number can't exceed sysconf(_SC_NGROUPS_MAX).
grouplist
An array of the supplementary group IDs that you want to assign to the calling process.
pid
The process ID of a child of the calling process, or 0 to set the groups for the calling process.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The setgroupspid() function sets the group access list of the process identified by pid to the array of group IDs in grouplist. This function lets you modify a child process's supplementary group set without having to set the parent's groups before spawning.

Note:
  • The process identified by pid must be a child of the calling process, must have been created by posix_spawn() or posix_spawnp() with the POSIX_SPAWN_HOLD flag set, and must not have yet received a SIGCONT.
  • In order to set new groups or delete existing groups, your process must have the PROCMGR_AID_SETGID ability enabled. For more information, see procmgr_ability().

Returns:

0, or -1 if an error occurred (errno is set).

Errors:

EFAULT
The grouplist argument isn't a valid pointer.
EINVAL
The value of gidsetsize is larger than sysconf(_SC_NGROUPS_MAX).
EPERM
One of the following occurred:
  • The calling process doesn't have the required permission; see procmgr_ability().
  • The process identified by pid isn't a child of the calling process.
  • The child process isn't held.

Classification:

QNX Neutrino

Safety:  
Cancellation point No
Interrupt handler No
Signal handler No
Thread Yes