All commands (14,187)

  • Remove trailing whitespaces (or tabs) from a text file

    This command is useful when you are programming, for example.


    -1
    sed -i 's/[ \t]\+$//g' file.txt
    elder · 2011-09-07 01:47:44 9
  • Show all groups user is a member of and other useful info


    -1
    net user USERNAME /domain
    shawn_abdushakur · 2014-01-02 20:22:46 7
  • my command for downloading delicious web links,

    just a alternative using a saved html file of all of my bookmarks. works well although it takes awhile.


    -1
    wget -r --wait=5 --quota=5000m --tries=3 --directory-prefix=/home/erin/Documents/erins_webpages --limit-rate=20k --level=1 -k -p -erobots=off -np -N --exclude-domains=del.icio.us,doubleclick.net -F -i ./delicious-20090629.htm
    bbelt16ag · 2009-07-02 01:46:21 7
  • CPU architecture details

    It works in every linux box Show Sample Output


    -1
    cat /proc/cpuinfo
    magicjohnson_ · 2010-09-24 09:27:58 3
  • OSX Terminal helper with tab completion, ssh tunneling, and now screen re-attach

    http://github.com/c3w/ash . a Ruby SSH helper script . reads a JSON config file to read host, FQDN, user, port, tunnel options . changes OSX Terminal profiles based on host 'type' USAGE: put 'ash' ruby script in your PATH modify and copy ashrc-dist to ~/.ashrc configure OSX Terminal profiles, such as "webserver", "development", etc run "ash myhostname" and away you go! v.2 will re-attach to a 'screen' named in your ~/.ashrc Show Sample Output


    -1
    ash prod<tab>
    c3w · 2012-05-12 19:51:02 8
  • ls


    -1
    ls
    yingkailiang · 2013-03-14 01:28:01 5
  • check your up to date delicious links.

    This commands queries the delicious api then runs the xml through xml2, grabs the urls cuts out the first two columns, passes through uniq to remove duplicates if any, and then goes into linkchecker who checks the links. the links go the blacklist in ~/.linkchecker/blacklist. please see the manual pages for further info peeps. I took me a few days to figure this one out. I how you enjoy it. Also don't run these api more then once a few seconds you can get banned by delicious see their site for info. ~updated for no recursive Show Sample Output


    -1
    curl -k https://Username:Password@api.del.icio.us/v1/posts/all?red=api | xml2| \grep '@href' | cut -d\= -f 2- | sort | uniq | linkchecker -r0 --stdin --complete -v -t 50 -F blacklist
    bbelt16ag · 2013-05-04 17:43:21 8
  • Find all files containing a word

    This is very similar to the first example except that it employs the 'exec' argument of the find command rather than piping the result to xargs. The second example is nice and tidy but different *NIXs may not have as capable a grep command.


    -1
    find . -name "*.php" -exec grep -il searchphrase {} \;
    unixmonkey7797 · 2010-01-16 05:09:30 4
  • identify big file

    first 10 big file


    -1
    du -s * | sort -nr | head
    chenge · 2010-05-13 12:21:22 4
  • Timelapse with ffmpeg (after symlinking pictures as per ffmpeg FAQ)


    -1
    ffmpeg -r 12 -i img%03d.jpg -sameq -s hd720 -vcodec libx264 -crf 25 OUTPUT.MP4
    brainstorm · 2013-05-04 18:46:36 9
  • hardcode dnsserver, no more rewriting of etc/resolv.conf

    The while loop is an overkill, it would be simpler to prevent the file to be modified. That said, none of the proposed solutions are such: a real one would go to the source of the problem.


    -1
    chkmod -w /etc/resolve.conf
    ntropia · 2018-05-14 16:25:47 165
  • Edit all files found having a specific string found by grep

    Make sure that find does not touch anything other than regular files, and handles non-standard characters in filenames while passing to xargs.


    -1
    find . -type f -exec grep -qi 'foo' {} \; -print0 | xargs -0 vim
    arcege · 2009-09-03 17:55:26 7
  • Pear install behind proxy

    Useful since "export http_proxy=blahblah:8080" doesn't seem to work with pear Show Sample Output


    -1
    pear config-set http_proxy http://myusername:mypassword@corporateproxy:8080
    KoRoVaMiLK · 2010-05-13 14:44:03 30
  • know which version of the program is installed on your Debian and derivatives

    Output: Version 3.2-0 (for example if you type # aptitude show bash | grep Vers Depends on the language of your distribution, because the name of the word "Version" in other languages may be different.


    -1
    aptitude show $PROGRAM | grep Vers
    aabilio · 2009-02-27 23:24:37 8
  • Get minimum, current, maximum possible resolution of Xorg


    -1
    xrandr -q | grep -w Screen
    hemanth · 2010-02-14 15:38:49 3
  • split a postscript file

    splits a postscript file into multiple postscript files. for each page of the input file one output file will be generated. The files will be numbered for example 1_orig.ps 2_orig.ps ... The psselect commad is part of the psutils package


    -1
    file=orig.ps; for i in $(seq `grep "Pages:" $file | sed 's/%%Pages: //g'`); do psselect $i $file $i\_$file; done
    damncool · 2010-09-24 19:44:32 4
  • A simple overview of memory usage refreshed at user designated intervals.

    This command shows a high level overview of system memory and usage refreshed in seconds. Change -n 10 to you desired refresh interval. Show Sample Output


    -1
    watch -n 10 free -m
    Darkstar · 2014-01-04 10:10:15 12
  • Find the full path of an already running process

    Uses the pid to get the full path of the process. Useful when you do not which command got picked from the path Show Sample Output


    -1
    readlink -f /proc/<pid>/cmdline
    naseer · 2009-05-26 10:09:03 23
  • Filenames ROT13

    This got a bit complicated, because I had to introduce an additional dot at the end that has to be removed again later.


    -1
    for each in *; do file="$each."; name=${file%%.*}; suffix=${file#*.}; mv "$each" "$(echo $name | rot13)${suffix:+.}${suffix%.}"; done
    hfs · 2010-03-20 16:11:12 6
  • Sort files in $PWD by year embedded anywhere in filename


    -1
    ls --color=never -1| grep -E "[0-9]{4}"|sed -re "s/^(.*)([0-9]{4})(.*)$/\2 \1\2\3/" | sort -r
    ysangkok · 2014-01-04 20:50:12 9
  • display only tcp


    -1
    netstat -4tnape
    gnuyoga · 2009-05-26 11:50:52 5
  • wget, tar xzvf, cd, ls

    Combines a few repetitive tasks when compiling source code. Especially useful when a hypen in a file-name breaks tab completion. 1.) wget source.tar.gz 2.) tar xzvf source.tar.gz 3.) cd source 4.) ls From there you can run ./configure, make and etc. Show Sample Output


    -1
    wtzc () { wget "$@"; foo=`echo "$@" | sed 's:.*/::'`; tar xzvf $foo; blah=`echo $foo | sed 's:,*/::'`; bar=`echo $blah | sed -e 's/\(.*\)\..*/\1/' -e 's/\(.*\)\..*/\1/'`; cd $bar; ls; }
    oshazard · 2010-01-17 11:25:47 3
  • Split a file into equal size chunks and archive to (e)mail account.

    This is just a little snippit to split a large file into smaller chunks (4mb in this example) and then send the chunks off to (e)mail for archival using mutt. I usually encrypt the file before splitting it using openssl: openssl des3 -salt -k <password> -in file.tgz -out file.tgz.des3 To restore, simply save attachments and rejoin them using: cat file.tgz.* > output_name.tgz and if encrypted, decrypt using: openssl des3 -d -salt -k <password> -in file.tgz.des3 -out file.tgz edit: (changed "g" to "e" for political correctness)


    -1
    split -b4m file.tgz file.tgz. ; for i in file.tgz.*; do SUBJ="Backup Archive"; MSG="Archive File Attached"; echo $MSG | mutt -a $i -s $SUBJ YourEmail@(E)mail.com
    tboulay · 2010-03-20 16:49:19 8
  • Find Out My Linux Distribution Name and Version


    -1
    if [ -x /etc/*-release ]; then cat /etc/*-release ; else cat /etc/*-version ; fi
    hugoeustaquio · 2011-06-22 14:09:24 3
  • Transfer files with rsync over ssh on a non-standard port.

    Transfer files with rsync over ssh on a non-standard port, showing a progress bar and resuming partial transfers.


    -1
    rsync -P -e 'ssh -p PORT' SRC DEST
    vickio · 2011-10-13 08:59:07 4
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list all files in a directory, sorted in reverse order by modification time, use file descriptors.
It's both silly, and infinitely useful. Especially useful in logfile directories where you want to know what file is being updated while troubleshooting.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

BASH: Print shell variable into AWK

See how many more processes are allowed, awesome!
There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

Count the total number of files in each immediate subdirectory
counts the total (recursive) number of files in the immediate (depth 1) subdirectories as well as the current one and displays them sorted. Fixed, as per ashawley's comment

for too many arguments by *
$ grep ERROR *.log -bash: /bin/grep: Argument list too long $ echo *.log | xargs grep ERROR /dev/null 20090119.00011.log:DANGEROUS ERROR

get total of inodes of root partition

A signal trap that logs when your script was killed and what other processes were running at that time
trap is the bash builtin that allows you to execute commands when the current script receives a particular signal. Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

take a look to command before action
add |sh when you agree the list, I often use that method to prevent typos in dangerous or long operations

Get gzip compressed web page using wget.
Like the original command, but the -f allows this one to succeed even if the website returns uncompressed data. From gzip(1) on the -f flag: If the input data is not in a format recognized by gzip, and if the --stdout is also given, copy the input data without change to the standard output: let zcat behave as cat.

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