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Commands tagged cat

Commands tagged cat from sorted by
Terminal - Commands tagged cat - 33 results
find /usr/include/ -name '*.[c|h]pp' -o -name '*.[ch]' -exec cat {} \;|wc -l
2011-12-01 19:58:52
User: kerim
Functions: cat find wc
-4

Count your source and header file's line numbers

For example for java change the command like this

find . -name '*.java' -exec cat {} \;|wc -l

for line in `cat $file`; do firefox -new-tab "$line" & 2>/dev/null; sleep 1; done
2011-11-12 13:47:24
User: hamsolo474
Functions: sleep
1

this will open a new tab in firefox for every line in a file

the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

cat x
cat -n file.txt
grep . *
2011-09-01 09:16:04
User: theist
Functions: grep
Tags: cat grep
18

If you have a bunch of small files that you want to cat to read, you can cat each alone (boring); do a cat *, and you won't see what line is for what file, or do a grep . *. "." will match any string and grep in multifile mode will place a $filename: before each matched line. It works recursively too!!

echo $(cat /usr/share/dict/words |grep -v "'"|shuf -n4)
2011-08-31 12:48:14
User: d1v3rdown
Functions: cat echo grep
Tags: cat echo grep shuf
0

Fast and excludes words with apostrophes. For ubuntu, you can use wamerican or wbritish dictionaries, installable through aptitude.

sort -R
2011-07-15 15:35:27
User: RyanM
Functions: sort
2

Randomizes a file. The opposite of sort is sort -R!

cat /dev/sda | pv -r > /dev/null
2011-01-23 22:58:56
User: kerim
Functions: cat
-1

Change your drive letter as you wish.

Using pv command for speed detect.First of all you must install pv command for usage.

http://www.bayner.com/

kerim@bayner.com

for _a in {A..Z} {a..z};do _z=\${!${_a}*};for _i in `eval echo "${_z}"`;do echo -e "$_i: ${!_i}";done;done|cat -Tsv
1

This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop.

I created a function for this and use it instead of env. (by aliasing env).

This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM.

aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; }

And my printenv replacement is:

alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"'

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

tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee
5

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount

cat file_with_tabs.txt | perl -pe 's/\t/ /g'
2010-07-11 13:01:22
User: nikc
Functions: cat perl
Tags: cat perl replace
-3

Replaces tabs in output with spaces. Uses perl since sed seems to work differently across platforms.

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
4
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)

cat file1 ... fileN > combinedFile;
2010-04-17 01:00:04
User: GinoMan2440
Functions: cat
Tags: cat bash Linux
-4

the last person who posted used the most roundabout way to concatinate files, there's a reason there's a "conCATinate" command... Using this method, you also get to choose the order of the files, below another person just did *.txt > combined.txt which is fine but the order depends on the implementation of "cat" which is probably alphabetical order of filenames.

perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt
ps aux | grep [h]ttpd | cat -n
2009-12-17 20:45:44
User: putnamhill
Functions: cat grep ps
Tags: cat
0

If you're on a system that doesn't have nl, you can use cat -n.

{ echo -e "$body"; uuencode "$outfile" "$outfile"; } | mail -s "$subject" "$destaddr" ;
2009-12-10 18:08:59
User: glaudiston
Functions: echo mail uuencode
Tags: cat mail
0

on this way we can define the body too

cat -n
cat </dev/tcp/time.nist.gov/13
2009-12-03 21:40:14
User: drewk
Functions: cat
Tags: cat tcp
8

The format is JJJJJ YR-MO-DA HH:MM:SS TT L DUT1 msADV UTC(NIST) OTM

and is explained more fully here: http://tf.nist.gov/service/acts.htm

cat /var/log/httpd/access_log | grep q= | awk '{print $11}' | awk -F 'q=' '{print $2}' | sed 's/+/ /g;s/%22/"/g;s/q=//' | cut -d "&" -f 1 | mail youremail@isp.com -s "[your-site] search strings for `date`"
2009-11-22 03:03:06
User: isma
Functions: awk cat grep sed strings
-2

It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.

dd if=/dev/hda of=file.img
cat /dev/hda > ~/hda.iso
random -f <file>
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-
cat filename | uuencode filename | mail -s "Email subject" user@example.com
2009-09-21 04:13:50
User: amaymon
Functions: cat mail uuencode
Tags: cat mail
0

uuencode the file to appear as an attachment

cat filename | mail -s "Email subject" user@example.com
2009-09-20 01:38:23
Functions: cat mail
Tags: cat mail
2

This just reads in a local file and sends it via email. Works with text or binary. *Requires* local mail server.