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          GETGRENT(3C)         INTERACTIVE UNIX System         GETGRENT(3C)



          NAME
               getgrent, getgrgid, getgrnam, setgrent, endgrent, fgetgrent
               - get group file entry

          SYNOPSIS
               #include <grp.h>

               struct group *getgrent ( )

               struct group *getgrgid (gid)
               int gid;

               struct group *getgrnam (name)
               char *name;

               void setgrent ( )

               void endgrent ( )

               struct group *fgetgrent (f)
               FILE *f;

          DESCRIPTION
               The getgrent, getgrgid, and getgrnam functions each return
               pointers to an object with the following structure contain-
               ing the broken-out fields of a line in the /etc/group file.
               Each line contains a ``group'' structure, defined in the
               <grp.h> header file.

               struct group {
                      char    *gr_name;   /* the name of the group */
                      char    *gr_passwd; /* the encrypted group password */
                      int     gr_gid;     /* the numerical group ID */
                      char    **gr_mem;   /* vector of pointers to member names */
               };

               The getgrent function when first called returns a pointer to
               the first group structure in the file; thereafter, it
               returns a pointer to the next group structure in the file;
               so, successive calls may be used to search the entire file.
               Getgrgid searches from the beginning of the file until a
               numerical group ID matching gid is found and returns a
               pointer to the particular structure in which it was found.
               Getgrnam searches from the beginning of the file until a
               group name matching name is found and returns a pointer to
               the particular structure in which it was found.  If an end-
               of-file or an error is encountered on reading, these func-
               tions return a NULL pointer.

               A call to setgrent has the effect of rewinding the group
               file to allow repeated searches.  Endgrent may be called to
               close the group file when processing is complete.



          Rev. C Software Development Set                            Page 1





          GETGRENT(3C)         INTERACTIVE UNIX System         GETGRENT(3C)



               Fgetgrent returns a pointer to the next group structure in
               the stream f, which matches the format of /etc/group.

          FILES
               /etc/group


















































          Rev. C Software Development Set                            Page 2





          GETGRENT(3C)         INTERACTIVE UNIX System         GETGRENT(3C)



          SEE ALSO
               getlogin(3C), getpwent(3C), group(4).

          DIAGNOSTICS
               A NULL pointer is returned on EOF or error.

          WARNING
               The above routines use <stdio.h>, which causes them to
               increase the size of programs, not otherwise using standard
               I/O, more than might be expected.

          CAVEAT
               All information is contained in a static area, so it must be
               copied if it is to be saved.









































          Rev. C Software Development Set                            Page 3



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