Commands by grahambuddhenry (0)

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create ext4 filesystem with big count of inodes
XX is your device partition number like /dev/sdc1 . to see how many inodes your partition have type: $ df --inodes (or df -i) Default formatting with ext4 would create small inode count for the new partition if you need big count of inodes is the fstype news the correct one. in debian you can see which fstype exists as template in: $ vim /etc/mke2fs.conf if you format default ext for a partition size with 1TB you would get 1 Million inodes (not enough for backupStorages) but if you format with fstype news you would get hunderd of millions of inodes for the partition. you have tune $/etc/sysctl.conf also with following sysconfig parameters $ fs.file-max = XXX $ fs.nr_open = XXX where XXX is the count of max inodes for whole system

Record audio and video from webcam using ffmpeg
Record from a webcam, audio using ALSA encoded as MP3, video as MPEG-4.

Create a self-extracting archive for win32 using 7-zip
using `cat` under *NIX - just because you help manage M$ Windoze *doesn't* mean you should have to resort to using it! You can also make custom win32 installers with the 7zip "extras" package: $ cat /path/to/7zSD.sfx /path/to/config.txt /path/to/archive > setup.exe

Look up a unicode character by name
[Update! Thanks to a tip from ioggstream, I've fixed both of the bugs mentioned below.] You, yes, 𝙔𝙊𝙐, can be the terror of the Internet! Why use normal, boring bullet points in your text, when you could use a ROTATED HEAVY BLACK HEART BULLET (❥)!? (Which would also be an awesome band name, by the way).  This script makes it easy to find unusual characters from the command line. You can then cut and paste them or, if you're using a GTK application, type Control+Shift+U followed by the code point number (e.g., 2765) and then a SPACE.  USAGE: Put this script in a file (I called mine "ugrep") and make it executable. Run it from the command line like so,  $ ugrep heart  The output will look like this,  ☙ U+2619 REVERSED ROTATED FLORAL HEART BULLET ♡ U+2661 WHITE HEART SUIT ♥ U+2665 BLACK HEART SUIT ❣ U+2763 HEAVY HEART EXCLAMATION MARK ORNAMENT ❤ U+2764 HEAVY BLACK HEART ❥ U+2765 ROTATED HEAVY BLACK HEART BULLET ❦ U+2766 FLORAL HEART ❧ U+2767 ROTATED FLORAL HEART BULLET ⺖ U+2E96 CJK RADICAL HEART ONE ⺗ U+2E97 CJK RADICAL HEART TWO ⼼ U+2F3C KANGXI RADICAL HEART  You can, of course, use regular expressions. For example, if you are looking for the "pi" symbol, you could do this:  $ ugrep '\bpi\b'  REQUIREMENTS: Although this is written in Bash, it assumes you have Perl installed because it greps through the Perl Unicode character name module (/usr/lib/perl5/Unicode/CharName.pm). Note that it would not have made more sense to write this in Perl, since the CharName.pm module doesn't actually include a subroutine for looking up a character based on the description. (Weird.)  BUGS: In order to fit this script in the commandlinefu limits, a couple bugs were added. ① Astral characters beyond the BMP (basic multilingual plane) are not displayed correctly, but see below. ② Perl code from the perl module being grepped is sometimes extraneously matched.  MISFEATURES: Bash's printf cannot, given a Unicode codepoint, print the resulting character to the terminal. GNU's coreutils printf (usually "/usr/bin/printf") can do so, but it is brokenly pedantic about how many hexadecimal digits follow the escape sequence and will actually die with an error if you give the wrong number. This is especially annoying since Unicode code points are usually variable length with implied leading zeros. The CharNames.pm file represents BMP characters as 4 hexits, but astral characters as 5. In the actual version of this script that I use, I've kludged around this misfeature by zero-padding to 8 hexits like so,  $ /usr/bin/printf "\U$(printf "%08x" 0x$hex)"  TIP 1: The author recommends "xsel" for command line cut-and-paste. For example,  $ ugrep biohazard | xsel  TIP 2: In Emacs, instead of running this command in a subshell, you can type Unicode code points directly by pressing Control-Q first, but you'll likely want to change the default input from octal to hexadecimal. (setq read-quoted-char-radix 16).  TIP 3: Of course, if you're using X, and you want to type one of the more common unusual characters, it's easiest of all to do it with your Compose (aka Multi) key. For example, hitting [Compose] <3 types ♥.

Set file access control lists
The file myfile is owned by tom and has read and write permissions for tom. Group and other permissions are empty which make myfile readable and writable only by tom. setfacl enables user tom to give read permission to user john only. The command 'ls -l' shows a '+' sign telling us that file access control list has been setup for myfile.

Fibonacci numbers with awk
Another combination of seq and awk. Not very efficient, but sufficiently quick.

Opens vi/vim at pattern in file
Open up vi or vim at the first instance of a pattern in [file]. Useful if you know where you want to be, like "PermitRootLogin" in sshd_config. Also, vi +10 [file] will open up a file at line 10. VERY useful when you get "error at line 10" type of output.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Recursive grep of all c++ source under the current directory
I like this better than some of the alternatives using -exec, because if I want to change the string, it's right there at the end of the command line. That means less editing effort and more time to drink coffee.

Randomize lines (opposite of | sort)
random(6) - random lines from a file or random numbers


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