Here's a comparison of the various methods proposed so far, with line numbers where possible:
Code:
$ awk '{print NR,$0}' test.txt # Not a solution, but to show the original file
1 This is a line
2 This is another line
3
4 The previous line is empty
5
6 The previous line contains whitespaces
7 # This shouldn't show
8 This should show again
$ grep -n ^[^#] test.txt
1:This is a line
2:This is another line
4:The previous line is empty
5:
6:The previous line contains whitespaces
8:This should show again
$ sed '/^#/d' test.txt
This is a line
This is another line
The previous line is empty
The previous line contains whitespaces
This should show again
$ grep -nv ^# test.txt
1:This is a line
2:This is another line
3:
4:The previous line is empty
5:
6:The previous line contains whitespaces
8:This should show again
$ grep -n "^[^#]*" test.txt
1:This is a line
2:This is another line
3:
4:The previous line is empty
5:
6:The previous line contains whitespaces
7:# This shouldn't show
8:This should show again
How can I delete those lines that starts with a certain letter?
abc def ghi
xyz abc def
ace gik moq
abe imq gxm
I want to delete the line that starts with "x". Thanks! (4 Replies)
Hi Guys,
I have an awk script that would search the input file for line that starts with a number 3 and copies into a new text file.
I want to extend this script to find the lines that either starts with 3 or a or b and copy all those lines into the new file.
Here is what I have so far:... (1 Reply)
Hi, I have one file, I need to check if file exist or not and then remove the lines which starts with ?
My file1.out data is some thing
abcabcppp
xyzxyzpqr
?????????
?????????
Output should be in test.out
abcabcppp
xyzxyzpqr
I am getting the output as below but the File does not exist... (4 Replies)
example:
comment Now_TB.table column errac is for error messages
1 - first
2 - second
3 -third ;
in this example I need to be able to grab the comment as first word and ; as the last word and it might span a few lines. I need it to be put all in one line without line breaks so I can... (4 Replies)
I have requirement in my every files starting lines have # needs to be not processing or exclude the that lines.
I have written a code like below, but now working as expected getting ERROR" line 60:
1 #!/bin/sh
2 echo ======= LogManageri start ==========
3
4 #This directory is... (1 Reply)
I have a file like below
#Fields section bald
1234 2345 456 222
abcs dddd dddd ssss
mmmm mmm mmm
i need do not process a files stating with #
I was written code below
while read -r line
do
if
then
echo ${line} >>
elif
then
... (3 Replies)
This is on a CentOS box, I have two scripts that need to run in order.
I want to write a shell script that calls the first script, lets it run and then terminates it after a certain number of hours (that I specify of course), and then calls the second script (they can't run simultaneously) which... (3 Replies)
Discussion started by: btramer
3 Replies
LEARN ABOUT DEBIAN
logtop
LOGTOP(1) General Commands Manual LOGTOP(1)NAME
logtop - Realtime log line rate analyser
SYNOPSIS
logtop [OPTIONS]
DESCRIPTION
logtop is a System Administrator tool analyzing line rate on stdin.
It reads on stdin and print a constantly updated result
displaying, in columns:
Line number, count, frequency, and the actual line.
$ tail -f FILE | logtop
is the friendly version of:
$ watch 'tail FILE | sort | uniq -c | sort -gr'
OPTIONS -s, --size=K
Only keep K lines in memory, instead of 10000.
-q, --quiet
Do not display a live view of the data, only display a top at exit.
-l, --line-by-line=K
Print result line by line, in a machine friendly format, K is the number of result to print per line.
Line by line format is : [%d %f %s ]*
%d : Number of occurences
%f : Frequency of apparition
%s : String (Control chars replaced by dots.
-i, --interval=K
Interval between graphical updates, in seconds. Defaults to 1.
-h, --help
Show summary of options.
-v, --version
Show version of program.
EXAMPLES
Here are some logtop usage examples.
tail -f cache.log | grep -o "HIT|MISS" | logtop
Realtime hit / miss ratio on some caching software log file.
tail -f access.log | cut -d' ' -f1 | logtop -s 10000
Realtime most querying IPs on your server, as long as log lines in access.log starts with the client IP.
tail -f access.log | cut -d' ' -f7 | logtop -s 10000
Realtime most requested web pages in a NCSA like log file.
cat auth.log | grep -v "CRON" | grep -o ": .*" | logtop -q -s 100000
Display a one-shot simple analyse of your auth.log.
SEE ALSO watch(1)AUTHOR
logtop was written by Julien Palard.
This manual page was written by Julien Palard <julien@palard.fr>, for the Debian project (and may be used by others).
April 16, 2011 LOGTOP(1)