Hello one-liners!

igadoter · 08-21-2018, 12:44 PM

I address in this way those who like to bash and try to avoid extensive use of scripts. So everyone is invited to post here its own one line (or maybe two line) compound command. Here what I mean

Code:

$ alias lspkg='ls /var/log/packages | grep '; lspkg pyth

this one-liner should list many python packages installed. Here more complicated example I just run

Code:

$ for f in $(ls *.c ) ; do if [ `wc -l $f | cut -d' ' -f1` -lt 200 ] ; then echo  $f ;  fi ; done

word of explanation: it just looks through c source files and picks those with less than 200 lines of code. Here is the output in coreutils/src directory

Code:

basename.c
coreutils-arch.c
coreutils-dir.c
coreutils-vdir.c
cp-hash.c
dirname.c
false.c
find-mount-point.c
force-link.c
getlimits.c
group-list.c
groups.c
hostid.c
hostname.c
lbracket.c
libstdbuf.c
link.c
logname.c
ls-dir.c
ls-ls.c
ls-vdir.c
mkfifo.c
nproc.c
operand2sig.c
printenv.c
prog-fprintf.c
readlink.c
relpath.c
sleep.c
true.c
tty.c
uname-arch.c
uname-uname.c
unlink.c
users.c
version.c
whoami.c
yes.c

Basically to be one-liner means for me to create such things on demand, definitely not to try to memorize or - even worse - put this in auto-magical script. Why I posting in this forum? Slackware is just very well suited for such way of work. I hope idea is quite clear.

Final word: I plan all these sources file to convert to pdf (text2pdf from slackbuilds) - to create one book - maybe with some comments of mine - and copy to my tablet - and of course read in my spare time. Of course for educational purposes.

bassmadrigal · 08-21-2018, 01:06 PM

I keep all my useful (to me) "one-liners" on my github (for easy access on other systems). They aren't all exactly one-liners, but if they aren't, they're close. If I didn't write them myself, I credit those who did in the file. Here's two I think others might benefit from:

This one I keep as file in my /usr/local/bin and it can find the same lines in files even if they aren't in order.

Code:

perl -ne 'print if ($seen{$_} .= @ARGV) =~ /10$/' $1 $2

I use this to download videos from youtube and automatically get the highest quality audio and video while sticking with mp4 format. I just store it in a folder that I download all the videos to and I simply call it get

Code:

/usr/bin/youtube-dl -f bestvideo[ext=mp4]+bestaudio[ext=m4a] $@

rkfb · 08-21-2018, 01:44 PM

A simple one:

Code:

cd ~/foo;clear;ls -lhB --color=auto;echo -ne "\n"

Change to the given directory and print a nice coloured list of the contents followed by a new line.

Turbocapitalist · 08-21-2018, 02:24 PM

Sometimes people ask about "all" the programs installed.

Code:

apropos -w '*' | awk '$2=="(8)"||$2=="(1)"' | sort | less

Keith Hedger · 08-21-2018, 02:29 PM

Some bash aliases that I use all the time

Code:

alias search='find . \! -iname '\''*~'\'' -print |xargs grep -s --ignore-case --binary-files=without-match --line-number'
alias get='history|grep -i'

'search' search's all files in current folder for a string.
'get' searches the bash history for a string.

This is sort of a one liner

Code:

show ()
{
	top -bn1|grep -i "$1"|awk '{print $1}'|xargs ps -ww
}

But has to be in a function to pass the param, shows all running procs matching string.

coralfang · 08-21-2018, 03:17 PM

Recursively count the total number of lines inside every matching file;

Code:

function wccat() { grep -r --include "$@" . | wc -l; }

eg;

Code:

$ wccat *.cpp
5427

Also here's 2 more.

Grep for running process names

Code:

function psgrep() { ps axuf | grep -v grep | grep "$@"; }

Read the slackware changelog

Code:

function slackclog() { curl -s ftp://ftp.osuosl.org/pub/slackware/slackware64-current/ChangeLog.txt | more; }