Commands by cfajohnson

Commands by cfajohnson (19)

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Print today's date in ISO format without calling an external command (bash 4)
This is sample output - yours may be different.
2

today() { printf '%(%Y-%m-%d)T\n' -1; } ## bash-4

cfajohnson · 2013-01-27 06:17:25 6
Get MD5 checksum from a pipe stream and do not alter it
This is sample output - yours may be different.
2

tee >(openssl md5 > sum.md5) <somefile | bzip2 > somefile.bz2

cfajohnson · 2013-01-27 05:59:14 8
List only files in long format.
This is sample output - yours may be different.
0

ls -l | grep ^-

cfajohnson · 2010-03-20 03:20:19 4
Turn shell tracing and verbosity (set -xv) on/off with 1 command!

Turn shell tracing and verbosity (set -xv) on/off in any Bourne-type shell If either -x or -v is set, the function turns them both off. If neither is on, both are turned on.
This is sample output - yours may be different.
4

xv() { case $- in *[xv]*) set +xv;; *) set -xv ;; esac }

cfajohnson · 2010-02-14 20:57:29 3
floating point shell calculator
This is sample output - yours may be different.
0

calc() { awk 'BEGIN { OFMT="%f"; print '"$*"'; exit}'; }

cfajohnson · 2009-12-25 19:08:16 5
Recursive chmod all files and directories within the current directory
This is sample output - yours may be different.
5

chmod -R 774 .

cfajohnson · 2009-12-23 18:42:26 6
Random colours at random locations
This is sample output - yours may be different.
2

p(){ printf "\033[%d;%dH\033[4%dm \033[m" $((RANDOM%LINES+1)) $((RANDOM%COLUMNS+1)) $((RANDOM%8)); }; clear;while :;do p; sleep .001;done

cfajohnson · 2009-12-17 15:25:28 3
Optimal way of deleting huge numbers of files
This is sample output - yours may be different.
3

find /path/to/dir/ -type f -exec rm {} +

cfajohnson · 2009-12-10 04:44:44 21
Get your public ip
This is sample output - yours may be different.
-3

wget -qO - http://cfaj.freeshell.org/ipaddr.cgi

cfajohnson · 2009-12-10 04:34:57 3
Extract all urls from the last firefox sessionstore.js file used.
This is sample output - yours may be different.
-1

sed -e 's/{"url":/\n&/g' ~/.mozilla/firefox/*/sessionstore.js | cut -d\" -f4

cfajohnson · 2009-12-10 04:31:31 4
List files that DO NOT match a pattern

There's no need for ls or grep; printf is builtin to most modern shells
This is sample output - yours may be different.
-1

printf "%s\n" !(pattern) ## ksh, or bash with shopt -s extglob

cfajohnson · 2009-11-26 14:09:56 3
Shell function to exit script with error in exit status and print optional message to stderr

USAGE: die ERRNUM [MESSAGE]
This is sample output - yours may be different.
7

die(){ result=$1;shift;[ -n "$*" ]&&printf "%s\n" "$*" >&2;exit $result;}

cfajohnson · 2009-11-23 22:26:43 9
Find all dot files and directories

In most modern shells, printf is a builtin command.
This is sample output - yours may be different.
0

printf "%s\n" .*

cfajohnson · 2009-11-23 18:07:18 3
Make sure a script is run in a terminal.

Exit with error if script is not run in a terminal
This is sample output - yours may be different.
21

[ -t 0 ] || exit 1

cfajohnson · 2009-11-20 23:14:49 10
Get your external IP address
This is sample output - yours may be different.
0

wget -qO - http://www.sputnick-area.net/ip;echo

cfajohnson · 2009-11-20 23:10:31 4
List all available commands (bash, ksh93)
This is sample output - yours may be different.
7

printf "%s\n" ${PATH//:/\/* }

cfajohnson · 2009-11-20 22:55:59 4
force change password for all user

This assumes that te original's 'passwd -e' forces a user to change password; it doesn't in the versions I have.
This is sample output - yours may be different.
0

while IFS=: read u x; do passwd -e "$u"; done < /etc/passwd

cfajohnson · 2009-11-20 21:49:34 7
Find all dot files and directories
This is sample output - yours may be different.
1

printf "%s\n" .*

cfajohnson · 2009-11-20 21:41:02 3
Show sorted list of files with sizes more than 1MB in the current dir
This is sample output - yours may be different.
1

ls -l | awk '$5 > 1000000' | sort -k5n

cfajohnson · 2009-11-20 21:18:45 7

What's this?

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Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X

I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: $ echo $'\33[H\33[2J'

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

list files recursively by size

rsync over ssh via non-default ssh port

tested on cygwin and Fedora 9 . good to remember for those jobs where you cannot set a site-specific connect option in your ~/.ssh/config file.

Show Shared Library Mappings

shows which shared lib files are pointed to by the dynamic linker.

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" }

Given process ID print its environment variables

Same as previous but compatible with BSD/IPSO

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

find all non-html files

Make backups recurse through directories

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