Allow comment to be placed at the end of a configuration line.

MFC after:	2 weeks

usr.sbin/syslogd/syslog.conf.5

@@ -406,6 +406,20 @@ normally the superuser.
 Blank lines and lines whose first non-blank character is a hash
 .Pq Dq #
 character are ignored.
+If
+.Ql #
+is placed in the middle of the line, the
+.Ql #
+character and the rest of the line after it is ignored.
+To prevent special meaning, the
+.Ql #
+character may be escaped with
+.Ql \e ;
+in this case preceding
+.Ql \e
+is removed and
+.Ql #
+is treated as an ordinary character.
 .Sh IMPLEMENTATION NOTES
 The
 .Dq kern

usr.sbin/syslogd/syslogd.c

@@ -1662,6 +1662,17 @@ init(int signo)
 			prog[i] = 0;
 			continue;
 		}
+		for (p = cline + 1; *p != '\0'; p++) {
+			if (*p != '#')
+				continue;
+			if (*(p - 1) == '\\') {
+				strcpy(p - 1, p);
+				p--;
+				continue;
+			}
+			*p = '\0';
+			break;
+		}
 		for (i = strlen(cline) - 1; i >= 0 && isspace(cline[i]); i--)
 			cline[i] = '\0';
 		f = (struct filed *)calloc(1, sizeof(*f));