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Terminal - Commands tagged line - 11 results
sed -n "/^.\{73,\}/p" < /path/to/file
2014-03-20 12:31:57
User: flatcap
Functions: sed
0

Filter out lines of input that contain 72, or fewer, characters.

"sed -n" : don't print lines by default

"/^.\{73,\}/" : find lines that start with 73 (or more) characters

"p" : print them

while read i; do [ ${#i} -gt 72 ] && echo "$i"; done < /path/to/file
2014-03-20 12:27:06
User: flatcap
Functions: echo read
1

Filter out lines of input that contain 72, or fewer, characters.

This uses bash only. ${#i} is the number of characters in variable i.

perl -nle 'print length,"\t",$_ if length > 37' < /path/to/input/file
tail -n +<N> <file> | head -n 1
2011-09-30 08:30:30
User: qweqq
Functions: head tail
-5

Tail is much faster than sed, awk because it doesn't check for regular expressions.

vi +4 /etc/mtab
2011-09-15 19:18:00
User: totti
Functions: vi
Tags: edit text line goto
1

This is not printing, real editing using the text editor.

perl -ne 'print if !$a{$_}++'
2011-02-17 02:18:44
User: doherty
Functions: perl
3

Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.

awk 'BEGIN{RS="\0"}{gsub(/\n/,"<SOMETEXT>");print}' file.txt
2010-12-12 21:43:22
User: __
Functions: awk
1

awk version of 7210. Slightly longer, but expanding it to catch blank lines is easier:

awk 'BEGIN{RS="\0"}{gsub(/\n+/,"<SOMETEXT>");print}' file.txt
find -name "*.<suffix>" -exec wc -l "{}" \; | sort -n | tail
2010-06-29 05:53:43
User: cooper
Functions: find sort wc
Tags: wc source java line
0

Find the source file which contains most number of lines in your workspace

:)

L(){ l=`builtin printf %${2:-$COLUMNS}s` && echo -e "${l// /${1:-=}}"; }
2

One of the first functions programmers learn is how to print a line. This is my 100% bash builtin function to do it, which makes it as optimal as a function can be. The COLUMNS environment variable is also set by bash (including bash resetting its value when you resize your term) so its very efficient. I like pretty-output in my shells and have experimented with several ways to output a line the width of the screen using a minimal amount of code. This is like version 9,000 lol.

This function is what I use, though when using colors or other terminal features I create separate functions that call this one, since this is the lowest level type of function. It might be better named printl(), but since I use it so much it's more optimal to have the name contain less chars (both for my programming and for the internal workings).

If you do use terminal escapes this will reset to default.

tput sgr0

For implementation ideas, check my

http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

shmore(){ local l L M="`echo;tput setab 4&&tput setaf 7` --- SHMore --- `tput sgr0`";L=2;while read l;do echo "${l}";((L++));[[ "$L" == "${LINES:-80}" ]]&&{ L=2;read -p"$M" -u1;echo;};done;}
2010-04-21 00:40:37
User: AskApache
Functions: echo read
6
SH
cat mod_log_config.c | shmore

or

shmore < mod_log_config.c

Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable.

What I wanted was a "more" pager that was basically the same as running:

cat file

Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output.

After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so

This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work.

One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the

tput setab 4; tput setaf 7

command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text.

This is one of hundreds of functions I have in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html">.bash_profile at http://www.askapache.com/">AskApache.com, but actually won't be included till the next update.

If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

find . -name "*.sql" -print0 | wc -l --files0-from=-
2009-06-22 17:45:03
User: vincentp
Functions: find wc
Tags: find wc count line
2

This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files.

The combination of print0 and files0-from options makes the whole command simple and efficient.