03-11-2013
Well, tail -f can be a problem to manage, but the file is the file. Data can get hung up in the pipe, too. Shell can find strings without calling grep, using case. Logs can be written in blocks from a FILE* buffer. You could poll and just tail a big hunk of file. You could figure how many lines you have checked and just check up-file of there. Really economical and efficient solutions would be in C, where you can mmap() the file as it growns and monitor the content with low overhead just in areas not already checked.
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because the tail +2 on the first line gives me the file name pomga I do not want anything like what I miss
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ouput
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1
2
3
4
5
6
7
8
9
10 (2 Replies)
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LEARN ABOUT DEBIAN
plan9-tail
TAIL(1) General Commands Manual TAIL(1)
NAME
tail - deliver the last part of a file
SYNOPSIS
tail [ +-number[lbc][rf] ] [ file ]
tail [ -fr ] [ -n nlines ] [ -c nbytes ] [ file ]
DESCRIPTION
Tail copies the named file to the standard output beginning at a designated place. If no file is named, the standard input is copied.
Copying begins at position +number measured from the beginning, or -number from the end of the input. Number is counted in lines, 1K
blocks or bytes, according to the appended flag or Default is -10l (ten ell).
The further flag causes tail to print lines from the end of the file in reverse order; (follow) causes tail, after printing to the end, to
keep watch and print further data as it appears.
The second syntax is that promulgated by POSIX, where the numbers rather than the options are signed.
EXAMPLES
tail file
Print the last 10 lines of a file.
tail +0f file
Print a file, and continue to watch data accumulate as it grows.
sed 10q file
Print the first 10 lines of a file.
SOURCE
/src/cmd/tail.c
BUGS
Tails relative to the end of the file are treasured up in a buffer, and thus are limited in length.
According to custom, option +number counts lines from 1, and counts blocks and bytes from 0.
Tail is ignorant of UTF.
TAIL(1)