Submitted by: Joachim Kuebart, thanks.

Add -u option to force unbuffered output

2 files changed, 23 insertions, 11 deletions

diff --git a/usr.bin/tr/tr.1 b/usr.bin/tr/tr.1
index 7779073..ae6b484 100644
--- a/usr.bin/tr/tr.1
+++ b/usr.bin/tr/tr.1
@@ -34,7 +34,7 @@
 .\"
 .\"     @(#)tr.1	8.1 (Berkeley) 6/6/93
 .\"
-.Dd June 6, 1993
+.Dd October 11, 1997
 .Dt TR 1
 .Os
 .Sh NAME
@@ -42,18 +42,18 @@
 .Nd translate characters
 .Sh SYNOPSIS
 .Nm tr
-.Op Fl cs
+.Op Fl csu
 .Ar string1 string2
 .Nm tr
-.Op Fl c
+.Op Fl cu
 .Fl d
 .Ar string1
 .Nm tr
-.Op Fl c
+.Op Fl cu
 .Fl s
 .Ar string1
 .Nm tr
-.Op Fl c
+.Op Fl cu
 .Fl ds
 .Ar string1 string2
 .Sh DESCRIPTION
@@ -82,6 +82,10 @@ or
 .Ar string2 )
 in the input into a single instance of the character.
 This occurs after all deletion and translation is completed.
+.It Fl u
+The
+.Fl u
+option guarantees that any output is unbuffered.
 .El
 .Pp
 In the first synopsis form, the characters in
@@ -290,3 +294,8 @@ has less characters than
 is permitted by POSIX but is not required.
 Shell scripts attempting to be portable to other POSIX systems should use
 the ``[#*]'' convention instead of relying on this behavior.
+The
+.Fl u
+option is an extension to the
+.St -p1003.2
+standard.
diff --git a/usr.bin/tr/tr.c b/usr.bin/tr/tr.c
index fd17637..52ccb1a 100644
--- a/usr.bin/tr/tr.c
+++ b/usr.bin/tr/tr.c
@@ -42,7 +42,7 @@ static const char copyright[] =
 static char sccsid[] = "@(#)tr.c	8.2 (Berkeley) 5/4/95";
 #endif
 static const char rcsid[] =
-	"$Id$";
+	"$Id: tr.c,v 1.6 1997/08/18 07:24:58 charnier Exp $";
 #endif /* not lint */
 
 #include <locale.h>
@@ -108,7 +108,7 @@ main(argc, argv)
 	(void) setlocale(LC_CTYPE, "");
 
 	cflag = dflag = sflag = 0;
-	while ((ch = getopt(argc, argv, "cds")) != -1)
+	while ((ch = getopt(argc, argv, "cdsu")) != -1)
 		switch((char)ch) {
 		case 'c':
 			cflag = 1;
@@ -119,6 +119,9 @@ main(argc, argv)
 		case 's':
 			sflag = 1;
 			break;
+		case 'u':
+			setbuf(stdout, (char *)NULL);
+			break;
 		case '?':
 		default:
 			usage();
@@ -262,9 +265,9 @@ static void
 usage()
 {
 	(void)fprintf(stderr, "%s\n%s\n%s\n%s\n",
-		"usage: tr [-cs] string1 string2",
-		"       tr [-c] -d string1",
-		"       tr [-c] -s string1",
-		"       tr [-c] -ds string1 string2");
+		"usage: tr [-csu] string1 string2",
+		"       tr [-cu] -d string1",
+		"       tr [-cu] -s string1",
+		"       tr [-cu] -ds string1 string2");
 	exit(1);
 }