Convert slstatus.1 to mandoc, simplify it and remove -h

We also change the semantics of -v to only return the version
information.
There is now no need for usage() to exit with anything other than 1.

slstatus.1

@@ -1,34 +1,38 @@
-.TH SLSTATUS 1 slstatus
+.Dd 2017-08-10
-.SH NAME
+.Dt SLSTATUS 1
-slstatus \- suckless status
+.Os suckless.org
-.SH SYNOPSIS
+.Sh NAME
-.B slstatus
+.Nm slstatus
-.RB [ \-dhov ]
+.Nd suckless status monitor
-.SH DESCRIPTION
+.Sh SYNOPSIS
-slstatus is a suckless and lightweight status monitor for window managers that use WM_NAME as statusbar (e.g. DWM) or any other status bars as long as they support reading from stdin. It is written in pure C without any extern programs being executed and only reads from files most of the time. slstatus is meant to be a better alternative to Bash scripts (inefficient) and Conky (bloated and written in C++).
+.Nm
-.SH OPTIONS
+.Oo
-.TP
+.Op Fl v
-.B \-d
+|
-run slstatus as daemon in background
+.Oo
-.TP
+.Op Fl d
-.B \-h
+.Op Fl o | n
-display help
+.Oc
-.TP
+.Oc
-.B \-o
+.Sh DESCRIPTION
-output continuously to console instead of WM_NAME
+.Nm
-.TP
+is a suckless status monitor for window managers that use WM_NAME (e.g. dwm) or
-.B \-n
+stdin to fill the status bar.
-output to console once and exit
+By default,
-.TP
+.Nm
-.B \-v
+outputs to WM_NAME.
-display version and copyright details
+.Sh OPTIONS
-.SH CUSTOMIZATION
+.Bl -tag -width Ds
-.B slstatus
+.It Fl d
+Daemonize.
+.It Fl n
+Write to stdout once and exit.
+.It Fl o
+Write to stdout continuously.
+.It Fl v
+Write version information to stdout and exit.
+.El
+.Sh CUSTOMIZATION
+.Nm
 can be customized by creating a custom config.h and (re)compiling the source
 code. This keeps it fast, secure and simple.
-.SH AUTHORS
-See the LICENSE file for the authors.
-.SH LICENSE
-See the LICENSE file for the terms of redistribution.
-.SH BUGS
-See the FIXME's in the code.

slstatus.c

@@ -70,7 +70,7 @@ static const char *vol_perc(const char *card);
 static const char *wifi_perc(const char *iface);
 static const char *wifi_essid(const char *iface);
 static void sighandler(const int signo);
-static void usage(const int eval);
+static void usage(void);
 
 char *argv0;
 static unsigned short int delay = 0;
@@ -838,10 +838,10 @@ sighandler(const int signo)
 }
 
 static void
-usage(const int eval)
+usage(void)
 {
 	fprintf(stderr, "usage: %s [-d] [-o] [-n] [-v] [-h]\n", argv0);
-	exit(eval);
+	exit(1);
 }
 
 int
@@ -865,16 +865,14 @@ main(int argc, char *argv[])
 			nflag = 1;
 			break;
 		case 'v':
-			printf("slstatus (C) 2016-2017 slstatus engineers\n");
+			printf("slstatus-"VERSION"\n");
 			return 0;
-		case 'h':
-			usage(0);
 		default:
-			usage(1);
+			usage();
 	} ARGEND
 
 	if ((dflag && oflag) || (dflag && nflag) || (oflag && nflag)) {
-		usage(1);
+		usage();
 	}
 	if (dflag && daemon(1, 1) < 0) {
 		err(1, "daemon");