pkt-line: drop safe_write function

This is just write_or_die by another name. The one
distinction is that write_or_die will treat EPIPE specially
by suppressing error messages. That's fine, as we die by
SIGPIPE anyway (and in the off chance that it is disabled,
write_or_die will simulate it).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/pkt-line.c b/pkt-line.c
index 5138f47..699c2dd 100644
--- a/pkt-line.c
+++ b/pkt-line.c
@@ -46,23 +46,6 @@
 	strbuf_release(&out);
 }
 
-ssize_t safe_write(int fd, const void *buf, ssize_t n)
-{
-	ssize_t nn = n;
-	while (n) {
-		int ret = xwrite(fd, buf, n);
-		if (ret > 0) {
-			buf = (char *) buf + ret;
-			n -= ret;
-			continue;
-		}
-		if (!ret)
-			die("write error (disk full?)");
-		die_errno("write error");
-	}
-	return nn;
-}
-
 /*
  * If we buffered things up above (we don't, but we should),
  * we'd flush it here
@@ -70,7 +53,7 @@
 void packet_flush(int fd)
 {
 	packet_trace("0000", 4, 1);
-	safe_write(fd, "0000", 4);
+	write_or_die(fd, "0000", 4);
 }
 
 void packet_buf_flush(struct strbuf *buf)
@@ -106,7 +89,7 @@
 	va_start(args, fmt);
 	n = format_packet(fmt, args);
 	va_end(args);
-	safe_write(fd, buffer, n);
+	write_or_die(fd, buffer, n);
 }
 
 void packet_buf_write(struct strbuf *buf, const char *fmt, ...)