Novice question on vectors of pointers

John J. Rushford Jr jjr at rushpc
Mon Apr 29 15:13:13 AEST 1991



I hope this question is not too OS specific.  Point me elsewhere if it is.

How does one use a vector of pointers to member names.  I'm specifically
trying to use getgrnam(3C) in UNIX SVR3.2 and I want to print to 'stdout'
all the entries in **gr_mem.  Below is an example of what I'm trying to
work with.  I don't have any problem with the remaining elements in the
structure.  It's **gr_mem I don't understand.  How do you work with it?

EXAMPLE:

#include <stdio.h>
	
/* From '/usr/include/grp.h'
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 pointer to member names */
	};

struct group *pntr, *getgrnam();

main()
{
	pntr = getgrnam("other");

	fprintf(stdout, "%s\n", pntr->gr_name);
	fprintf(stdout, "%s\n", pntr->gr_passwd);
	fprintf(stdout, "%d\n", pntr->gr_gid);
	

	return 0;
}


thanks a ton.
-- 

John
----
Westminster Colorado	



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