From e565522068410c57707592a3f1586381865ab69c Mon Sep 17 00:00:00 2001
From: Connor Lane Smith <cls@lubutu.com>
Date: Sat, 4 Jun 2011 02:56:18 +0100
Subject: [PATCH] ln -f

---
 ln.1    |  7 +++++--
 ln.c    | 23 ++++++++++++++++++++---
 uname.c |  2 +-
 3 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/ln.1 b/ln.1
index beacd1e..4205ea7 100644
--- a/ln.1
+++ b/ln.1
@@ -3,12 +3,12 @@
 ln \- make links between files
 .SH SYNOPSIS
 .B ln
-.RB [ \-s ]
+.RB [ \-fs ]
 .I file
 .RI [ name ]
 .P
 .B ln
-.RB [ \-s ]
+.RB [ \-fs ]
 .RI [ file ...]
 .RI [ directory ]
 .SH DESCRIPTION
@@ -18,6 +18,9 @@ it is linked into the current directory.  If multiple files are listed they will
 be linked into the given directory.
 .SH OPTIONS
 .TP
+.B \-f
+remove existing destinations.
+.TP
 .B \-s
 create a symlink.
 .SH SEE ALSO
diff --git a/ln.c b/ln.c
index e61bb7c..8016084 100644
--- a/ln.c
+++ b/ln.c
@@ -1,23 +1,40 @@
 /* See LICENSE file for copyright and license details. */
+#include <errno.h>
 #include <stdbool.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include "util.h"
 
+static int ln(const char *, const char *);
+
+static bool sflag = false;
+static bool fflag = false;
+
 int
 main(int argc, char *argv[])
 {
-	bool sflag = false;
 	char c;
 
-	while((c = getopt(argc, argv, "s")) != -1)
+	while((c = getopt(argc, argv, "fs")) != -1)
 		switch(c) {
+		case 'f':
+			fflag = true;
+			break;
 		case 's':
 			sflag = true;
 			break;
 		default:
 			exit(EXIT_FAILURE);
 		}
-	enmasse(argc - optind, &argv[optind], sflag ? symlink : link);
+	enmasse(argc - optind, &argv[optind], ln);
 	return EXIT_SUCCESS;
 }
+
+int
+ln(const char *s1, const char *s2)
+{
+	if(fflag && remove(s2) != 0 && errno != ENOENT)
+		eprintf("remove %s:", s2);
+	return (sflag ? symlink : link)(s1, s2);
+}
diff --git a/uname.c b/uname.c
index 75ff52a..49fbda5 100644
--- a/uname.c
+++ b/uname.c
@@ -40,7 +40,7 @@ main(int argc, char *argv[])
 		default:
 			exit(EXIT_FAILURE);
 		}
-	if(uname(&u) == -1)
+	if(uname(&u) != 0)
 		eprintf("uname:");
 
 	if(sflag || !(nflag || rflag || vflag || mflag))