From 36e2bdf517773553053571a787ba720bcbfec367 Mon Sep 17 00:00:00 2001
From: "Roberto E. Vargas Caballero" <k0ga@shike2.com>
Date: Fri, 1 Jan 2016 18:25:58 +0100
Subject: [PATCH] ed: Use TMPDIR to locate the temporal file

The current behaviour of storing the scratch file in
the current directory is a bit painful, because it
generates files in all the directories where you
execute ed. BSD ed uses TMPDIR for this purpouse,
so if the user wants to put the scratch file in
other place different of /tmp it only has to set
this variable.
---
 ed.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/ed.c b/ed.c
index 1ecd0d9..62f8477 100644
--- a/ed.c
+++ b/ed.c
@@ -329,15 +329,17 @@ static void
 setscratch()
 {
 	int k;
+	char *dir;
 
 	clearbuf();
 	clearundo();
-	strcpy(tmpname, "ed.XXXXXX");
+	if ((dir = getenv("TMPDIR")) == NULL)
+		dir = "/tmp/";
+	if (strlen(dir) + sizeof("ed.XXXXXX") > FILENAME_MAX)
+		error("incorrect scratch file name");
+	strcat(strcpy(tmpname, dir), "ed.XXXXX");
 	if ((scratch = mkstemp(tmpname)) < 0) {
-		/* try /tmp if cwd is not writable */
-		strcpy(tmpname, "/tmp/ed.XXXXXX");
-		if ((scratch = mkstemp(tmpname)) < 0)
-			error("failed to create scratch file");
+		error("failed to create scratch file");
 	}
 	if ((k = makeline("", NULL)))
 		error("input/output error in scratch file");