Commands by bbbco (13)

  • Plain old `unzip` won't unzip output coming from STDOUT the ZIP file format includes a directory (index) at the end of the archive. This directory says where, within the archive each file is located and thus allows for quick, random access, without reading the entire archive. This would appear to pose a problem when attempting to read a ZIP archive through a pipe, in that the index is not accessed until the very end and so individual members cannot be correctly extracted until after the file has been entirely read and is no longer available. As such it appears unsurprising that most ZIP decompressors simply fail when the archive is supplied through a pipe. The directory at the end of the archive is not the only location where file meta information is stored in the archive. In addition, individual entries also include this information in a local file header, for redundancy purposes. From the `jar` manpage: > The jar command is a general-purpose archiving and compression tool, based on ZIP and the ZLIB compression format. JAR is smart enough to know how to handle these local file headers when the index is unavailable when reading through the pipe. (Most of the explanation in this description is taken from https://serverfault.com/a/589528/314226 , though they recommend using `bsdtar`, but that is not always available on systems) Show Sample Output


    0
    cat foo.zip | jar xv
    bbbco · 2019-01-14 22:08:19 34
  • Use dots to cd down directories instead of having to remember all of the pesky back slashes! Better yet, works on even and odd number of dots! Now, just estimate how far down you want to traverse. Show Sample Output


    1
    for i in {1..6};do c=;d=;for u in `eval echo {1..$i}`;do c="$c../";d="$d..";eval "$d(){ cd $c;}"; eval "$d.(){ cd $c;}";done;done
    bbbco · 2013-09-04 20:12:45 10

  • 12
    sudo dmidecode | grep Product
    bbbco · 2012-02-07 16:26:23 23
  • If you have ever edited a locally checked out version of a file to tweak it for testing purposes, and came back to it over a weekend, you might have forgotten what you exactly changed. This command helps you see the differences between the the checked in SVN version, and the one you tweaked. Show Sample Output


    0
    svn diff <FILE>
    bbbco · 2012-01-30 16:47:48 15
  • Ever need to get some text that is a specific number of characters long? Use this function to easily generate it! Doesn't look pretty, but sure does work for testing purposes! Show Sample Output


    0
    genRandomText() { a=( a b c d e f g h i j k l m n o p q r s t u v w x y z );f=0;for i in $(seq 1 $(($1-1))); do r=$(($RANDOM%26)); if [ "$f" -eq 1 -a $(($r%$i)) -eq 0 ]; then echo -n " ";f=0;continue; else f=1;fi;echo -n ${a[$r]};done;echo"";}
    bbbco · 2012-01-20 21:18:16 5
  • Prints a string indicating whether a command is an alias, keyword, function, builtin, or file. I have used this in my BASH scripts to allow an external parameter to define which function to run, and ensure that it is a valid function that can indeed be run. Show Sample Output


    1
    type -t $1
    bbbco · 2012-01-10 21:57:29 6
  • Use the -a flag to display all files, including hidden files. If you just want to display regular files, use a -1 (yes, that is the number one). Got this by RTFM and adding some sed magic. [bbbco@bbbco-dt ~]$ ls -a | sed "s#^#${PWD}/#" /home/bbbco/. /home/bbbco/.. /home/bbbco/2011-09-01-00-33-02.073-VirtualBox-2934.log /home/bbbco/2011-09-10-09-49-57.004-VirtualBox-2716.log /home/bbbco/.adobe /home/bbbco/.bash_history /home/bbbco/.bash_logout /home/bbbco/.bash_profile /home/bbbco/.bashrc ... [bbbco@bbbco-dt ~]$ ls -1 | sed "s#^#${PWD}/#" /home/bbbco/2011-09-01-00-33-02.073-VirtualBox-2934.log /home/bbbco/2011-09-10-09-49-57.004-VirtualBox-2716.log /home/bbbco/cookies.txt /home/bbbco/Desktop /home/bbbco/Documents /home/bbbco/Downloads ... Show Sample Output


    -9
    ls -a | sed "s#^#${PWD}/#"
    bbbco · 2011-12-16 22:19:06 7
  • Sometimes you need the full path to your script, regardless of how it was executed (which starting directory) in order to maintain other relative paths in the script. If you attempt to just use something simple like: STARTING_DIR="${0%/*}" you will only get the relative path depending on where you first executed the script from. You can get the relative path to the script (from your starting point) by using dirname, but you actually have to change directories and print the working directory to get the absolute full path. Show Sample Output


    0
    STARTING_DIR=$(cd $(dirname $0) && pwd)
    bbbco · 2011-11-30 17:35:15 6
  • Get a listing of all of your databases in Postgres and their sizes, ordering by the largest size first. Requires that you give the -d parameter a valid database name that you can connect to. Show Sample Output


    6
    psql -c "SELECT pg_database.datname, pg_database_size(pg_database.datname), pg_size_pretty(pg_database_size(pg_database.datname)) FROM pg_database ORDER BY pg_database_size DESC;" -d <ANYDBNAME>
    bbbco · 2011-11-30 15:22:48 6
  • Even simpler! Use du ... the -s and -c flags summarize and print a grand total of all files recursively. The -b flag prints in byte format. You can use the -h flag instead to print in human readable format. Show Sample Output


    2
    du -scb
    bbbco · 2011-06-27 14:20:11 119
  • Ever need to erase the contents of a file and start over from scratch? This easy command allows you to do so. Be warned! This will immediately erase all the contents of your file and start you over from scratch (i.e. your file will be at 0 bytes, like if you touch a file). Show Sample Output


    -3
    > [filename]
    bbbco · 2011-05-18 14:59:02 8
  • This is just a slight alternative that wraps all of #7917 in a function that can be executed Show Sample Output


    2
    anagram(){ s(){ sed 's/./\n\0/g'<<<$1|sort;};cmp -s <(s $1) <(s $2)||echo -n "not ";echo anagram; }; anagram foobar farboo;
    bbbco · 2011-02-17 15:10:43 7
  • Sets an alias to remote desktop to the specified console, along with options to ensure the RDP session takes up the whole screen, includes a home directory mapping, and clipboard mappings. Show Sample Output


    0
    alias rdp='rdesktop -u <user> -g 1600x1200 -D -r disk:home=/home -r clipboard:PRIMARYCLIPBOARD'
    bbbco · 2011-02-04 16:22:49 4

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grep certain file types recursively
-exec works better and faster then using a pipe

happened to find this not bad software to keep my files and folders safe! Even the free trial version has the fantastic functions to protect any private files from being seen by anyone except me. With it I can encrypt, hide or lock anything I want, amazin
I noticed some spammer posted an advertisement here for "not bad" encryption. Unfortunately, their software only runs under Microsoft Windows and fails to work from the commandline. My shell script improves upon those two aspects, with no loss in security, using the exact same "military-grade" encryption technology, which has the ultra-cool codename "ROT-13". For extra security, I recommend running ROT-13 twice.

quickly rename a file

Start a local web server in the current directory on a random dynamic port.

Randomize lines (opposite of | sort)
Randomizes a file. The opposite of sort is sort -R!

Google Translate
$ translate [output-language] [source-language] 1) "some phrase" should be in quotes 2) [output-language] - optional (default: English) 3) [source-language] - optional (default: auto) $ translate "bonjour petit lapin" hello little rabbit $ translate "bonjour petit lapin" en hello little rabbit $ translate "bonjour petit lapin" en fr hello little rabbit

Umount only the NFS related to 'string'
Sometimes, you have a lot of NFS in the server and you can't or shouldn't use umount -a. Whis this command, you only umount the fs related to the 'string'

add all files not under version control to repository
This should handle whitespaces well and will not get confused if your filenames have "?" in them

Pretty-print user/group info for a given user

Find the package that installed a command


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