GETGROUPS(2)
NAME
getgroups − get group access list
SYNTAX
#include <sys/param.h>
getgroups(ngroups, gidset)
int *ngroups, *gidset;
DESCRIPTION
Getgroups gets the current group access list of the user process and stores it in the array gidset. The parameter ngroups indicates the number of entries which may be placed in gidset and is modified on return to indicate the actual number of groups returned. No more than NGRPS, as defined in <sys/param.h>, will ever be returned.
A value of 0 indicates that the call succeeded, and that the number of elements of gidset and the set itself were returned. A value of −1 indicates that an error occurred, and the error code is stored in the global variable errno.
DIAGNOSTICS
The possible errors for getgroup are:
[EFAULT] The arguments ngroups or gidset specify invalid addresses.