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INITGROUPS(3)            BSD Library Functions Manual            INITGROUPS(3)

     initgroups -- initialize group access list

     Standard C Library (libc, -lc)

     #include <unistd.h>

     initgroups(const char *name, int basegid);

     The initgroups() function uses the getgrouplist(3) function to calculate the group access list for the
     user specified in name.  This group list is then setup for the current process using setgroups(2).  The
     basegid is automatically included in the groups list.  Typically this value is given as the group num-ber number
     ber from the password file.

     The initgroups() function returns -1 if it was not invoked by the super-user.

     setgroups(2), getgrouplist(3)

     The initgroups() function appeared in 4.2BSD.

     The getgrouplist() function called by initgroups() uses the routines based on getgrent(3).  If the
     invoking program uses any of these routines, the group structure will be overwritten in the call to

BSD                              June 4, 1993                              BSD

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