docs/logging_and_backgrounding.txt: new mini-doc

dnsd: remove statics, remove nerly-useless SIGINT handler
crond: correct more of logfile to 0666 (as usual, umask allows
 user to remove unwanted bits).
nameif: print errors to stderr too, not just to syslog

function                                             old     new   delta
udhcp_read_interface                                 308     306      -2
ttl                                                    4       -      -4
fileconf                                               4       -      -4
dnsentry                                               4       -      -4
interrupt                                             19       -     -19
dnsd_main                                           1463    1394     -69
------------------------------------------------------------------------------
(add/remove: 0/4 grow/shrink: 0/2 up/down: 0/-102)           Total: -102 bytes
   text    data     bss     dec     hex filename
 808161     476    7864  816501   c7575 busybox_old
 807994     468    7856  816318   c74be busybox_unstripped

1 files changed, 1 insertions, 3 deletions

diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index 15b31eb3d..a82fd8c47 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -46,12 +46,10 @@ int udhcpd_main(int argc UNUSED_PARAM, char **argv)
 
         opt = getopt32(argv, "fS" USE_FEATURE_UDHCP_PORT("P:", &str_P));
         argv += optind;
-
         if (!(opt & 1)) { /* no -f */
                 bb_daemonize_or_rexec(0, argv);
-                logmode &= ~LOGMODE_STDIO;
+                logmode = LOGMODE_NONE;
         }
-
         if (opt & 2) { /* -S */
                 openlog(applet_name, LOG_PID, LOG_DAEMON);
                 logmode |= LOGMODE_SYSLOG;