Change the exit value on errors to be more 4.4BSD like. Use the sum of

errors up to a maximum of 127, then to do not increment anymore,
though programme execution continues.

Use 127 as a maximum because error codes above this are:

1. bad because of signed bugs in programs.
2. used as the traditional shell $? representation of "kill by signal"
   where $? = 128 + signal.

(from deraadt@ and guenther@ respectively)

2 files changed, 10 insertions, 7 deletions

diff --git a/usr.bin/fmt/fmt.1 b/usr.bin/fmt/fmt.1
index c4a83454dff..068e1ecee7d 100644
--- a/usr.bin/fmt/fmt.1
+++ b/usr.bin/fmt/fmt.1
@@ -1,4 +1,4 @@
-.\" $OpenBSD: fmt.1,v 1.23 2012/01/15 11:43:45 schwarze Exp $
+.\" $OpenBSD: fmt.1,v 1.24 2012/01/17 04:26:28 lum Exp $
 .\"
 .\" Copyright (c) 1980, 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -29,7 +29,7 @@
 .\"
 .\"     @(#)fmt.1	8.1 (Berkeley) 6/6/93
 .\"
-.Dd $Mdocdate: January 15 2012 $
+.Dd $Mdocdate: January 17 2012 $
 .Dt FMT 1
 .Os
 .Sh NAME
@@ -149,6 +149,8 @@ evening the lines:
 .Ex -std
 The latter happens with invalid options, insufficient memory,
 or when an input file is not found or not readable.
+The >0 exit value is the sum of all errors up to a maximum of 127,
+more errors may occur but the counter will only increment to this number.
 .Sh SEE ALSO
 .Xr indent 1 ,
 .Xr mail 1 ,
diff --git a/usr.bin/fmt/fmt.c b/usr.bin/fmt/fmt.c
index 40aa65edc12..4a6cc1909ff 100644
--- a/usr.bin/fmt/fmt.c
+++ b/usr.bin/fmt/fmt.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fmt.c,v 1.28 2012/01/15 11:43:45 schwarze Exp $	*/
+/*	$OpenBSD: fmt.c,v 1.29 2012/01/17 04:26:28 lum Exp $	*/
 
 /* Sensible version of fmt
  *
@@ -243,6 +243,7 @@ static void	*xrealloc(void *, size_t);
 void		usage(void);
 
 #define XMALLOC(x) xrealloc(0, x)
+#define ERRS(x) (x >= 127 ? 127 : ++x)
 
 /* Here is perhaps the right place to mention that this code is
  * all in top-down order. Hence, |main| comes first.
@@ -340,7 +341,7 @@ main(int argc, char *argv[])
 	}
 
 	/* We're done. */
-	return n_errors ? EX_NOINPUT : 0;
+	return n_errors;
 
 }
 
@@ -353,7 +354,7 @@ process_named_file(const char *name)
 
 	if ((f = fopen(name, "r")) == NULL) {
 		warn("%s", name);
-		++n_errors;
+		ERRS(n_errors);
 	} else {
 		process_stream(f, name);
 		fclose(f);
@@ -462,7 +463,7 @@ process_stream(FILE *stream, const char *name)
 	new_paragraph(output_in_paragraph ? last_indent : first_indent, 0);
 	if (ferror(stream)) {
 		warn("%s", name);
-		++n_errors;
+		ERRS(n_errors);
 	}
 }
 
@@ -627,7 +628,7 @@ center_stream(FILE *stream, const char *name)
 
 	if (ferror(stream)) {
 		warn("%s", name);
-		++n_errors;
+		ERRS(n_errors);
 	}
 }