Console / shell tips & tricks

[Bones McCracker]

duh!

http://www.amazon.com/How-Win-Friends-I ... 0671723650

eww! Who reads all that

People who used to say "duh!" when offering someone a tip?

[swimmer]

duh!

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echo "bindkey "^R"                history-incremental-search-backward
bindkey "^S"                history-incremental-search-forward" >> .zshrc
. .zshrc

Luckily I don't know what "duh!" means and I think I don't want to know

Thanks for the tip ppurka

[Alanceil]

Why didn't I find this thread earlier ? *beats himself*
There were some really nice gems in here. ( Feels like "You just gained a level in Bash Magic!" )

In return, part of my bash config:

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shopt -s cdspell
shopt -u extdebug

complete -d cd
complete -c which
complete -c man
complete -c killall

alias ..='cd ..'
alias ...='cd ../..'
alias ....='cd ../../..'
alias .....='cd ../../../..'
alias l='ls -lF --color=always'
alias la='ls -la --color=always'
alias lh='ls -lh --color=always'
alias ll='ls -l --color=always'
alias ls='ls --color=always'
alias lS='ls -lS'
alias c='cd'
alias o='/usr/bin/less'
alias vo='/usr/bin/vim'
alias bi='/usr/bin/vim'
alias vu='/usr/bin/vim'
alias suvi='sudo /usr/bin/vim'
alias xc='/usr/bin/xv'

PS1='\[\033[0;32m\]\u@\h\[\033[0m\]:\[\033[0;36m\]\A\[\033[0m\]:\[\033[1;30m\]${?}\[\033[0m\]:\[\033[1;34m\]\w\[\033[0m\]>\[\033[0m\] '

I sometimes hit the wrong keys when I want to start vi, so there are some aliases to catch that. (In case you ask)

[ppurka]

I sometimes hit the wrong keys when I want to start vi, so there are some aliases to catch that. (In case you ask)

I believe there is some shell setting which makes the shell suggest you the correct alternative if you had a typo in the previous command.

[purpler]

oh yes, that setting is called ZSH

/etc/zsh/zshrc:
setopt correctall

[Alanceil]

Then I'll still have to use my vi aliases
I tried zsh several times, and never liked it.

... and sth. for the topic:

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function path(){
        test -e "$1" && echo "`pwd`/${1}"
}

[Dralnu]

oh yes, that setting is called ZSH

/etc/zsh/zshrc:
setopt correctall

bash has a similar feature.

[arcanex]

BashFAQ

http://wooledge.org:8000/BashFAQ

BashPitfalls

http://wooledge.org:8000/BashPitfalls

Between them, just about everything you might ever want to know about BASH.

[MartyParish]

Hey, here's a list that contains plenty of stuff that's been mentioned already but some stuff that I did not see. I read the whole thread too! It was great.

Ctrl + A - Go to the beginning of the line you are currently typing on

Ctrl + E - Go to the end of the line you are currently typing on

Ctrl + L - Clears the Screen, similar to the clear command

Ctrl + U - Clears the line before the cursor position. If you are at the end of the line, clears the entire line.

Ctrl + H - Same as backspace

Ctrl + R - Let’s you search through previously used commands

Ctrl + C - Kill whatever you are running

Ctrl + D - Exit the current shell

Ctrl + Z - Puts whatever you are running into a suspended background process. fg restores it.

Ctrl + W - Delete the word before the cursor

Ctrl + K - Clear the line after the cursor

Ctrl + T - Swap the last two characters before the cursor

Esc + T - Swap the last two words before the cursor

Alt + F - Move cursor forward one word on the current line

Alt + B - Move cursor backward one word on the current line

Tab - Auto-complete files and folder names

Ctrl + W - erase word before cursor

Ctrl + Y - to paste it (as in delete and copy) all text in front of the cursor

Esc + . (or Esc + Underscore) - Insert Last Argument

Ctrl + b - Move back a character

Ctrl + f - Move forward a character

Ctrl + r - Search the history backwards

Ctrl + xx - Move between EOL and current cursor position

Ctrl + x @ - Show possible hostname completions

Alt + < - Move to the first line in the history

Alt + > - Move to the last line in the history

Alt + ? - Show current completion list

Alt + * - Insert all possible completions

Alt + / - Attempt to complete filename

Alt + . - Yank last argument to previous command

Alt + c - Capitalize the word

Alt + d - Delete word

Alt + l - Make word lowercase

Alt + n - Search the history forwards non-incremental

Alt + p - Search the history backwards non-incremental

Alt + r - Recall command

Alt + t - Move words around

Alt + u - Make word uppercase

Alt + back-space - Delete backward from cursor

Here "2T" means Press TAB twice

$ 2T - All available commands(common)

$ (string) 2T - All available commands starting with (string)

$ /2T - Entire directory structure including Hidden one

$ 2T - Only Sub Dirs inside including Hidden one

$ *2T - Only Sub Dirs inside without Hidden one

$ ~2T - All Present Users on system from "/etc/passwd"

$ $2T - All Sys variables

$ @2T - Entries from "/etc/hosts"

$ =2T - Output like ls or dir

[devsk]

put this in your ~/.bashrc if you just want to override part of the DIR_COLORS and don't want to copy the full file to ~/.dir_colors and maintain it in future if /etc/DIR_COLORS changes:

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eval `cat /etc/DIR_COLORS ~/.dir_colors | dircolors -

[David Serrano]

Great thread!!

Also, using the ":p" option on any potentially-dangerous bash replacement tricks is useful: it prints out the command that WOULD be run and also appends it to your history. That is, if you think you want to run the last command starting with 'r' in your history but don't want to hose yourself before verifying the command:

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$ !r:p
rm -rf /

I use:

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shopt -s histverify

With this, you get confirmation for all history expansions. That's useful not only for verifying potentially harmful 'rm' commands, but also to change some parameters, files and whatever before actually running the command.

Here are my aliases and functions:

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function del() {
  /bin/mv -f "$@" $HOME/.trash/;
}
alias cd='cd -P'
alias ls='ls -F -N --color=tty --time-style="+%Y%m%d:%H%M%S%z"'
alias ll='ls -l'
alias cl='clear; logout'
alias cv='clear; vlock -a'
alias lless='ll -R --color=always | less -r'
## allows 'h emerge -s' without quoting the space
function h() { HISTTIMEFORMAT= history | grep "$*"; }

alias ltrace='ltrace -S -tt -C'
alias strace='strace -s 500 -tt -ff'
alias vim='vim -X -o'
alias bc='bc ~/.bcrc'  ## set up default number of decimals, .bcrc contains "scale=4"
alias perl='perl -Mstrict -w'
alias pf='perldoc -f'
alias pd='perldoc'
alias pq='perldoc -q'
alias xev='xev | grep keycode'

function rmoz() {
    ## ripped from      https://bugzilla.mozilla.org/attachment.cgi?id=151958
    ## which appears in https://bugzilla.mozilla.org/show_bug.cgi?id=246168
    if [ "$1" ]; then 
        if [ -f "$PWD/$1" ]; then
            LOCAL="file://$PWD/$1"
        elif [ -f "$1" ]; then 
            LOCAL="file://$1"
        else 
            LOCAL="$1"
            [[ $LOCAL =~ ^http:// ]] || LOCAL="http://$LOCAL"
        fi
        DISPLAY=:0 mozilla -remote "openurl($LOCAL,new-tab)"
    fi
}
## show version of specified perl modules
function pmver() { perl -le "eval { require ${1} } and print qq{${1}: },\$${1}::VERSION or print qq{${1}: none}"; }
function ls-() { ls -"$@"; }

Environment variables:

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export HISTCONTROL=ignoredups:erasedups
export HISTIGNORE="date:df:fg:jd:jobs:ll:ls"
export HISTTIMEFORMAT="%Y%m%d:%H%M%S%z"
export IGNOREEOF=1
export LESS='-c -h1 -y1 -j2 -S'
export LESS="$LESS -P B%bt-%bB?B/%B.?pt(%pt\%). ?ltL%lt-%lb.?L/%L.?Pt(%Pt\%). .?f%f:-.?e (END).?m (file %i of %m).%t"
unset LESSOPEN  ## hate this
## use with 'ps -eH' or 'ps -e f'
export PS_FORMAT="pid,pgid,euid,egid,nlwp:2=NT,ni:2,rtprio:2=RT,cls:2,vsz:6,rss:6,pcpu,pmem,stat:3=ST,tname:6,stime,bsdtime,args"
export TIMEFORMAT=$'\nreal: %3R, user: %3U, sys: %S'
export TMPDIR=~/tmp
export TMP=$TMPDIR

unset PERL5LIB;
DIRS=(~/em/perl-modules/{lib,share}/perl/*);
local IFS=":";
export PERL5LIB="${DIRS[*]}";

Misc:

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shopt -s cdable_vars checkhash checkwinsize cmdhist extquote histappend histreedit histverify
shopt -u force_fignore

if [[ "`tty`" =~ ^/dev/tty ]]; then  ## things for console only
  setterm -blength 10 -bfreq 10000   ## barely hearable, prevents waking up people
fi

.inputrc:

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set horizontal-scroll-mode off
## 'audible' or 'visible'
set bell-style audible
set meta-flag on
set input-meta on
set output-meta on
set convert-meta off
set history-preserve-point on
set editing-mode vi-command
set keymap vi-command
set page-completions off
set visible-stats on
## todo: yank-nth-arg
## todo: yank-last-arg

.xbindkeysrc:

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"xkbcomp /home/hue/.hue-xkb/es-qwerty-hue :0"
  control+F1

"xkbcomp /home/hue/.hue-xkb/es-dvorak-hue :0"
  control+F2

"xwd -root -silent | convert xwd:- png:/home/hue/xwd-$(date +%Y%m%d:%H%M%S.png)"
 Print

The ~/.hue-xkb files were generated by using xkbcomp; then further tweaked. It's like using xmodmap.

Last, I'd like to bump this excellent tip (not for obtaining the IP, but for its use of 'set'):

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alias currentip='set `/sbin/ifconfig eth0` && echo ${7#*:}'

[faux]

Nice thread. Read the whole one, really useful!

Job Management

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%<job ID>

recalls a running or suspended job.

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jobs

lists jobs of current session.
Ctrl+Z suspends current job and sends it to background.

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<command> &

starts a job in backgroud.

screen usage in my .bashrc

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if [ $SHLVL -eq 1 ]; then
  /usr/bin/screen -xRR
fi

Resumes the last screen session (or starts a new one, if nothing to resume) if using an tty (not a terminal like xterm) or SSH session. Very useful on SSH sessions if connection times out.

view ebuild of package

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eview() {
        FILE=$(equery which $1)
        if [ -f "$FILE" ]; then
                view $FILE
        fi
}

[notHerbert]

It has happened that I mistyped an append command in an important file.

My desire is to do something like this

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echo "some configuration" >> /etc/somefile

But instead I type

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echo "some configuration" > /etc/somefile

Consider

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# echo "something something" > /etc/passwd

This command would overwrite /etc/passwd, and would be a real pain to repair - even if the error is caught before logging out.


If I add this to .bashrc (then source .bashrc)

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set -o noclobber

Then I can do this

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# echo "a bunch of crap" > /etc/passwd
-su: /etc/passwd: cannot overwrite existing file

Now I caught my typo before making a mess.

Now if my intention really is to overwrite a file, a pipe character will allow me to do that.
To clear the contents of $HOME/.xsession-errors, type

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$ :>| $HOME/.xsession-errors

[a.b.]

The only interesting things in my .zshrc are:

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# With -p, Paludis should have normal niceness
# Else, it should be extremly friendly
function paludis(){
    if echo $@ | egrep '\-.*p\ ' > /dev/null; then
        /usr/bin/paludis $@
    else
        nice -n19 /usr/bin/paludis $@
    fi
}

and

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# For the really bullish processes
function murder(){
    while [[ $? = 0 ]]; do
        kill -9 $@
    done
}

The rest:
http://shellium.org/~aeebee/dotfiles/zshrc

[a.b.]

It has happened that I mistyped an append command in an important file.

That has happened to me several times as well. Backups more or less solve that

[notHerbert]

A bash command prompt that prints the return value in the prompt if it is not equal to zero.

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PS1='\w \u$(r=$?; test $r -ne 0 && echo " \[\e[1;31m\]ret:$r")\e[0m\] \$ '

[mv]

A bash command prompt that prints the return value in the prompt

This is once more an example why it is wiser to use zsh as the interactive shell. There you can just include %? or (for analogous behaviour to your case) %(?||ret:%?) within PS1 (coloring omitted for simplicity). Or even simpler and IMHO more convenient for daily usage: setopt print_exit_value.

[Dralnu]

renice <nice_value> `pgrep <proccess to renice>`

Or

renice <nice_val> $(pgrep <proc>) if you don't want the folks in #bash to yell at you

[a.b.]

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function wi() { vi $(equery which $@) 

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function usegrep() { grep $@ /var/repos/*/profiles/use.* }

and a couple of functions like

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function bugz() { if [[ $1 == get ]]; then =bugz $@ | less; else =bugz $@; fi }

[Dralnu]

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function usegrep() { grep $@ /var/repos/*/profiles/use.* }

I don't have a var/repos dir on my system. Are you talking about /usr/portage/profiles/use.desc?

[a.b.]

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function usegrep() { grep $@ /var/repos/*/profiles/use.* }

I don't have a var/repos dir on my system. Are you talking about /usr/portage/profiles/use.desc?

I've put the stuff in more logical places:

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# Folders
REPODIR="/var/repos"
PORTDIR="$REPODIR/gentoo"
PORTDIR_OVERLAY="$REPODIR/local $REPODIR/imported"
source "/var/repos/.layman/make.conf"
DISTDIR="/var/cache/distfiles"

In the default setup it's of course /usr/portage/etc..

[Ormaaj]

deleteme

[loudmax]

Here's my prompt string:

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PS1='\[\033[01;32m\]\u@\[\033[01;31m\]\h[\w]:`if [[ $? != 0 ]]; then echo "( "; else echo ") "; fi`\[\033[00m\]'

If the previous command succeeds it shows me it's happy:

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user@host[~]:) /bin/true 
user@host[~]:)

If the previous command fails, it's sad

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user@host[~]:) /bin/false
user@host[~]:( 

[nendzd]

^^^^ That is great!

Unfortunately I don't have any tips and tricks to post, although I am getting a lot of use out of this thread, thanks!

[coolsnowmen]

Here's my prompt string:

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PS1='\[\033[01;32m\]\u@\[\033[01;31m\]\h[\w]:`if [[ $? != 0 ]]; then echo "( "; else echo ") "; fi`\[\033[00m\]'

If the previous command succeeds it shows me it's happy:

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user@host[~]:) /bin/true 
user@host[~]:)

If the previous command fails, it's sad

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user@host[~]:) /bin/false
user@host[~]:( 

HAHAHAHAHHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA
edit: my most recent alias -

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alias ghistory="history | grep"
alias gh="ghistory"