only print the "no database" message once

[unix-history] / usr / src / lib / libc / gen / devname.c

/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* %sccs.include.redist.c%
*/

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)devname.c   5.11 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <fcntl.h>
#include <ndbm.h>
#include <stdio.h>
#include <paths.h>

char *
devname(dev)
       dev_t dev;
{
       static DBM *db;
       static int failure;
       datum dp, key;

       if (!db && !failure && !(db = dbm_open(_PATH_DEVDB, O_RDONLY, 0))) {
               (void)fprintf(stderr,
                   "ps: no device database %s\n", _PATH_DEVDB);
               failure = 1;
       }
       if (failure)
               return("??");

       key.dptr = (char *)&dev;
       key.dsize = sizeof(dev);
       dp = dbm_fetch(db, key);
       return(dp.dptr ? dp.dptr : "??");
}