sbase

commit 5765a6e6b434ce692a15ed2e64bc2ea0d1c5a2e1
parent 08b8c73ddaf92727f8e9a93f2c0d60eb0183caa4
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Sat, 13 Dec 2025 12:05:39 +0100

ed: Implement non truncate writes

The trunc parameter of dowrite() was ignored, making no difference
between the w and W commands.

Diffstat:
M
ed.c
 | 
4
+++-
A
tests/0018-ed.sh
 | 
20
++++++++++++++++++++

2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/ed.c b/ed.c
@@ -761,6 +761,7 @@ dowrite(const char *fname, int trunc)
 	FILE *aux;
 	static int sh;
 	static FILE *fp;
+	char *mode;
 
 	if (fp) {
 		sh ? pclose(fp) : fclose(fp);
@@ -774,7 +775,8 @@ dowrite(const char *fname, int trunc)
 			error("bad exec");
 	} else {
 		sh = 0;
-		if ((fp = fopen(fname, "w")) == NULL)
+		mode = (trunc) ? "w" : "a";
+		if ((fp = fopen(fname, mode)) == NULL)
 			error("cannot open input file");
 	}
 
diff --git a/tests/0018-ed.sh b/tests/0018-ed.sh
@@ -0,0 +1,20 @@
+#!/bin/sh
+
+tmp=tmp.$$
+
+trap 'rm -f $tmp' EXIT
+trap 'rm -f $tmp; kill -KILL $$' HUP INT TERM
+
+touch $tmp
+../ed -s $tmp <<EOF | (read a && test $a = 1)
+a
+1
+.
+w
+,c
+2
+.
+W
+e
+1p
+EOF