adjusted per comments from uwe, to match head (and gnu)
code copied matching head.
add options to tail:
-q (never print header of filename)
-v (always print header of filename)
same as head, same as gnu tail
add tac which is like tail -rq
Index: Makefile
===================================================================
RCS file: /cvsroot/src/usr.bin/tail/Makefile,v
retrieving revision 1.3
diff -u -r1.3 Makefile
--- Makefile 23 Nov 1994 07:41:55 -0000 1.3
+++ Makefile 1 Oct 2017 17:03:33 -0000
@@ -1,7 +1,8 @@
# $NetBSD: Makefile,v 1.3 1994/11/23 07:41:55 jtc Exp $
# @(#)Makefile 8.1 (Berkeley) 6/6/93
-
PROG= tail
SRCS= forward.c misc.c read.c reverse.c tail.c
+LINKS= ${BINDIR}/tail ${BINDIR}/tac
+
.include <bsd.prog.mk>
Index: tail.1
===================================================================
RCS file: /cvsroot/src/usr.bin/tail/tail.1,v
retrieving revision 1.17
diff -u -r1.17 tail.1
--- tail.1 4 Jul 2017 07:04:50 -0000 1.17
+++ tail.1 1 Oct 2017 17:03:33 -0000
@@ -32,7 +32,7 @@
.\"
.\" @(#)tail.1 8.1 (Berkeley) 6/6/93
.\"
-.Dd June 15, 2014
+.Dd October 1, 2017
.Dt TAIL 1
.Os
.Sh NAME
@@ -43,7 +43,7 @@
.Oo
.Fl f |
.Fl F |
-.Fl r
+.Fl rqv
.Oc
.Oo
.Fl b Ar number |
@@ -133,12 +133,17 @@
option is to display all of the input.
.El
.Pp
-If more than a single file is specified, each file is preceded by a
+If more than a single file is specified, or the
+.Fl v
+option is used, each file is preceded by a
header consisting of the string
.Dq ==> XXX \*[Le]=
where
.Dq XXX
is the name of the file.
+The
+.Fl q
+flag disables the printing of the header in all cases.
.Sh EXIT STATUS
.Ex -std tail
.Sh SEE ALSO
Index: tail.c
===================================================================
RCS file: /cvsroot/src/usr.bin/tail/tail.c,v
retrieving revision 1.17
diff -u -r1.17 tail.c
--- tail.c 31 Jan 2013 23:09:06 -0000 1.17
+++ tail.c 1 Oct 2017 17:03:33 -0000
@@ -67,6 +67,8 @@
enum STYLE style;
int ch, first;
char *p;
+ int qflag = 0;
+ int vflag = 0;
setprogname(argv[0]);
off = 0;
@@ -105,30 +107,45 @@
obsolete(argv);
style = NOTSET;
- while ((ch = getopt(argc, argv, "Fb:c:fn:r")) != -1)
- switch(ch) {
- case 'F':
- fflag = 2;
- break;
- case 'b':
- ARG(512, FBYTES, RBYTES);
- break;
- case 'c':
- ARG(1, FBYTES, RBYTES);
- break;
- case 'f':
- fflag = 1;
- break;
- case 'n':
- ARG(1, FLINES, RLINES);
- break;
- case 'r':
- rflag = 1;
- break;
- case '?':
- default:
- usage();
- }
+ if (strcmp(getprogname(), "tail") == 0) {
+ while ((ch = getopt(argc, argv, "Fb:c:fn:rqv")) != -1)
+ switch(ch) {
+ case 'F':
+ fflag = 2;
+ break;
+ case 'b':
+ ARG(512, FBYTES, RBYTES);
+ break;
+ case 'c':
+ ARG(1, FBYTES, RBYTES);
+ break;
+ case 'f':
+ fflag = 1;
+ break;
+ case 'n':
+ ARG(1, FLINES, RLINES);
+ break;
+ case 'r':
+ rflag = 1;
+ break;
+ case 'q':
+ qflag = 1;
+ vflag = 0;
+ break;
+ case 'v':
+ qflag = 0;
+ vflag = 1;
+ break;
+ case '?':
+ default:
+ usage();
+ }
+ } else { /* tac */
+ qflag = 1;
+ vflag = 0;
+ rflag = 1;
+ }
+
argc -= optind;
argv += optind;
@@ -169,7 +186,7 @@
ierr();
continue;
}
- if (argc > 1) {
+ if (vflag || (qflag == 0 && argc > 1)) {
(void)printf("%s==> %s <==\n",
first ? "" : "\n", fname);
first = 0;
@@ -299,7 +316,7 @@
usage(void)
{
(void)fprintf(stderr,
- "Usage: %s [-f | -F | -r] [-b # | -c # | -n #] [file ...]\n",
+ "Usage: %s [-f | -F | -rqv] [-b # | -c # | -n #] [file ...]\n",
getprogname());
exit(1);
}
