tail: fix -c +N. Closes 4111

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2011-09-17 00:12:24 +02:00
parent 6d2d652cd3
commit 0851d125c3
2 changed files with 11 additions and 3 deletions

View File

@ -203,7 +203,7 @@ int tail_main(int argc, char **argv)
int fd = fds[i]; int fd = fds[i];
if (ENABLE_FEATURE_FANCY_TAIL && fd < 0) if (ENABLE_FEATURE_FANCY_TAIL && fd < 0)
continue; /* may happen with -E */ continue; /* may happen with -F */
if (nfiles > header_threshhold) { if (nfiles > header_threshhold) {
tail_xprint_header(fmt, argv[i]); tail_xprint_header(fmt, argv[i]);
@ -252,14 +252,14 @@ int tail_main(int argc, char **argv)
* Used only by +N code ("start from Nth", 1-based): */ * Used only by +N code ("start from Nth", 1-based): */
seen = 1; seen = 1;
newlines_seen = 0; newlines_seen = 0;
while ((nread = tail_read(fd, buf, tailbufsize-taillen)) > 0) { while ((nread = tail_read(fd, buf, tailbufsize - taillen)) > 0) {
if (G.from_top) { if (G.from_top) {
int nwrite = nread; int nwrite = nread;
if (seen < count) { if (seen < count) {
/* We need to skip a few more bytes/lines */ /* We need to skip a few more bytes/lines */
if (COUNT_BYTES) { if (COUNT_BYTES) {
nwrite -= (count - seen); nwrite -= (count - seen);
seen = count; seen += nread;
} else { } else {
char *s = buf; char *s = buf;
do { do {

View File

@ -14,4 +14,12 @@ testing "tail: +N with N > file length" \
"0\n" \ "0\n" \
"" "qw" "" "qw"
testing "tail: -c +N with largish N" \
"
dd if=/dev/zero bs=16k count=1 2>/dev/null | tail -c +8200 | wc -c;
dd if=/dev/zero bs=16k count=1 2>/dev/null | tail -c +8208 | wc -c;
" \
"8185\n8177\n" \
"" ""
exit $FAILCOUNT exit $FAILCOUNT