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Commands tagged Text Processing from sorted by
Terminal - Commands tagged Text Processing - 37 results
cat ~/SortedFile.txt | perl -wnl -e '@f=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'
2009-09-24 15:42:43
User: drewk
Functions: cat perl
0

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-
function catv { egrep -v "^$|^#" ${*} ; }
2009-09-11 14:58:47
User: mobidyc
Functions: egrep
1

better integration.

works on all Unices

works one bash and ksh.

grep -PL "\t" -r . | grep -v ".svn" | xargs sed -i 's/\t/ /g'
2009-05-28 08:52:14
User: root
Functions: grep sed xargs
3

Note that this assumes the application is an SVN checkout and so we have to throw away all the .svn files before making the substitution.

fold -s -w 90 file.txt
2009-05-11 23:00:25
User: vincentp
Functions: fold
11

wraps text lines at the specified width (90 here).

-s option is to force to wrap on blank characters

-b count bytes instead of columns

nl filename | more
2009-05-04 07:35:16
User: haivu
Functions: nl
-2

The nl command lists the contents of a file where is each line is prefixed by a line number. For more information about this command, check out its man page. I tested under Mac OS X and Xubuntu 9.04

:split <file>
2009-02-25 23:41:22
User: raphink
4

You can then switch from a file to another with ^W^W

tail -1000 /some/file | vim -
2009-02-25 11:43:27
User: root
Functions: tail vim
17

The hyphen tells vim to open from STDOUT - saves having to create temporary files.

echo "foo bar" | sudo tee -a /path/to/some/file
2009-02-18 13:54:25
User: raphink
Functions: echo sudo tee
3

This is the solution to the common mistake made by sudo newbies, since

sudo echo "foo bar" >> /path/to/some/file

does NOT add to the file as root.

Alternatively,

sudo echo "foo bar" > /path/to/some/file

should be replaced by

echo "foo bar" | sudo tee /path/to/some/file

And you can add a >/dev/null in the end if you're not interested in the tee stdout :

echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null
grep -v "^\($\|#\)" <filenames>
2009-02-16 21:40:09
User: raphink
Functions: grep
2

Filter comments and empty lines in files. I find this very useful when trying to find what values are actually set in a very long example config file.

I often set an alias for it, like :

alias nocomment='grep -v "^\($\|#\)"'

diff dir1 dir2 | diffstat
2009-02-16 21:21:16
User: raphink
Functions: diff
0

See which files differ in a diff, and how many changes there are. Very useful when you have tons of differences.

sed -i '10d' <somefile>
2009-02-16 15:05:29
User: raphink
Functions: sed
4

Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.

sed '1000000!d;q' < massive-log-file.log
2009-01-26 11:50:00
User: root
Functions: sed
18

Sed stops parsing at the match and so is much more effecient than piping head into tail or similar. Grab a line range using

sed '999995,1000005!d' < my_massive_file