Useful shell scripts.
- txthole - Simple netcat-based pastebin server (also see beans)
- iwpick - Connects to a network.
- scrapthumb - Get random images from Tumblr.
- acpi - Simple power management.
- dwmstatus - Output useful informations suitable for a status bar.
- spawncgi - Spawn the CGI daemon.
- pronunciask - Get pronunciations from forvo.com.
- pkgsetup - Easy pkgsrc (and -wip) for non-NetBSD systems.
- whexsafe - Web safe color list in hex and RGB.
- swss - Start/stop a group of services.
- droid - Sane Android development. deprecated.
- dbrowse - Little dmenu-based file browser.
- diffmon - Diff-based file monitor.
- sober - Simple sobriety checker.
- mkbkp - Simple backups.
- setmon - Switch to HDMI video/audio if any.
- moin - Play a random song from a YouTube playlist.
- fetchpic - Fetch a random pic from a random blog (of a given list).
- sendpush - Send a PUSH notification via xdroid API
- wally - Change random wallpapers taken from the web
Store and retrieve text stream. Superseded by beans. Given the script is up and running, here's a sample usage:
$ echo Hello |nc your.host 2023
http://your.host/GmKwL
echo GmKwL |nc your.host 2023
$ echo GmKwL |nc your.host 2023
Hello
Of course you can also paste files:
$ cat /tmp/t |nc your.host 2023
You can set hostname when starting txthole, like this:
$ TXTHOLE_PUBHOST=my.public.host txthole &
If it's unset then txthole will only output the code instead of the whole command:
$ txthole &
$ echo Hello |nc your.host 2023
A1Syh
This should be enough for most use cases.
To serve content over HTTP, use something like this (nginx):
server {
root /tmp/pastes/;
server_name your.host;
index txthole.index.paste;
location / {
rewrite ^/([-.a-zA-Z0-9]+)$ "/txthole.$1.paste" last;
}
location ~ \.paste$ {
add_header Content-Type text/plain;
}
}
Take care of applying the right user/permission to the pastes directory:
# chgrp www-data /tmp/pastes
# chmod g+srx /tmp/pastes # s used to keep group
Connects to a network. Authentication is not mandatory and only WPA2 is supported at the moment. It will works with no pain on any Linux system equipped with iwconfig, sdhcp and wpa_supplicant. Just run:
$ sudo iwpick -e MyWirelessNetwork -k MyWPA2key
You may also use an aliases file (default ~/.networks), like this:
home:MyHomeNetwork:MyHomePassword
lucky:PublicNetwork
Then use the alias to connect:
$ sudo iwpick -a home
Connect to the first known network available:
$ sudo iwpick -p
TIP: $ chmod og-rwx ~/.networks
I'm considering if implement or not a flag to connects to the best possible network. The priority should be, descending order: private known networks, public known networks, public unknown networks. Networks with higher security and/or signal have higher priority. For now it's just an idea.
Known issues
- sdhcp may wait forever if the network interface don't have an IP address assigned. The workaround is to assign an IP address to the interface before run iwpick. Note: the address must be a valid IP for the network; this may be changed by sdhcp.
- The
/etc/resolv.confis not update by iwpick so you'll have to put your nameservers there by hand. Alternatively, you can edit the iwpick script and remove the -d flag for sdhcp.
Get random images from Tumblr.
Note: currently not working due to the recent Tumblr redirect to the new privacy policy, which you need to accept.
Some sample usages in ~/.xinitrc:
# Change wallpaper each 5 minutes
while true; do
feh --bg-max $(/path/of/scrapthumb -rn1)
sleep 5m
done &
# Change wallpaper each 5 minutes by storing the source into
# /tmp/.scrapthumb (new with the -u flag)
while true; do
t="$(/path/of/scrapthumb -urn1)"
src=$(echo $t |cut -d'|' -f1)
img=$(echo $t |cut -d'|' -f2)
feh --no-fehbg --bg-fill "$img"
echo "$t" > /tmp/.scrapthumb
sleep 5m
done &
If the image is in GIF format then the first frame is used (i.e. no playing at all). You can solve this by splitting frames up with convert(1) and set each of them as background with an interval of ~0.01 seconds. A better approach would be to use mpv with the --wid=0 parameter which is less CPU intensive.
You can achieve more extreme results by using scrapthumb in conjunction with semi-automatic customization tools. Have a look at autotheme.sh.
Notice the user if the battery charge is below 12% or suspend (in memory) the system if the battery is below 9%. Make it runs each minute via cron like this:
* * * * * sudo -i /path/of/acpi
It uses xmessage(1) and play(1) to alert the user.
Output useful informations suitable for a status bar. It's designed for dwm. Obsolete: use slstatus instead.
Sample output:
B:89%+ T:56C W:70% V:95% (0.23 0.21 0.22 0.16) 25/09/2015 11:15
Here is a brief explanations of the fields:
- B: battery percentage. A trailing symbol indicates that AC power is plugged (+) or not (-)
- T: temperature in celsius degrees
- W: wireless signal
- V: volume. A trailing asterisk indicates if the mute is on
- Load average between parenthesis
- Date and time
To set the dwm bar you have to call xsetroot, like this:
xsetroot -name "$(/path/of/dwmstatus)"
It's easy to auto-update the bar by putting this in your ~/.xinitrc:
while true; do
xsetroot -name "$(/path/of/dwmstatus)"
sleep 30s
done &
Spawn the CGI daemon.
Get pronunciations from forvo.com. Written for fun.
Managing pkgsrc bootstrapping and installation on non-NetBSD systems. Also supports pkgsrc-wip.
Generates the web safe colors list in hex and RGB formats.
Simple web stack switch. It just tiny script to start and stop a group of services which I use to deal with my web stack (redis, mysql, nginx, etc.).
Sane Android Development. Note: this script is deprecated, see below.
$ droid
Usage: droid <cmd>
Commands:
setup : creates the development environment
install : install the app into the device
upload : upload the app into the device
build : build the app (if no task, assumes assembleDebug)
upgrade : build and install the app (assembleDebug)
deploy : build and install the app (assembleRelease)
init : create a new project into the current directory
clean : remove all builds
help : print this help
You can now achieve the same results using the great sdkmanager tool along with gradle on the command line. In fact, I started to use those tools and I will not work on droid anymore.
Little dmenu-based file browser which output the selected files (if any).
Sample usage (for a single file):
$ mimeopen "$(/path/of/dbrowse)"
For dwm users, it may come in handy a key binding like this:
{ MODKEY|ShiftMask, XK_o, spawn, SHCMD("mimeopen -n \"$(/path/of/dbrowse)\"") },
Multiple selections are also supported.
Simple script which monitor a file and show lines that are changed since you ran it.
Simple sobriety checker inspired by DrunkGuard.
In a nutshell:
$ sudo rm -rf /
How much is 7 + 1? 8
How much is 5 + 9? 12
You're drunk, I'll take care of you.
Use sober by creating aliases in your ~/.${SHELL}rc file:
alias sudo="/path/of/sober sudo"
alias rm="/path/of/sober rm"
alias mv="/path/of/sober mv"
alias apt-get="/path/of/sober apt-get"
alias dpkg="/path/of/sober dpkg"
You may want to toggle this aliases at specific times (e.g. after work hours). This is easily achievable with simple shell scripts.
Copy all tracked files and git repositories into a directory. The stuff to backup is taken from the file given as argument or ${HOME}/.mkbkprc if no argument is given.
Sample configuration:
# default destination path if not given
BKPDIR="backup-$(hostname -s)-$(date +'%Y%m%d')"
# files and directories
NAMES="
${HOME}/myfiles
${HOME}/mail
${HOME}/.config/chromium/Default/Bookmarks
"
# git repositories
GITREPOS="
[email protected]:clamiax/scripts.git
"
onfinish() {
t="$1.tar.bz2"
echo -n "Compressing to $t..."
tar jcf "$t" "$1"
echo " done"
echo -n "Uploading to a backup server..."
scp "$t" user@host:/path/of/backup
echo " done"
echo "Completed."
}
mkbkp only supports backup of files, directories and git repositories. Though it easy to add support for virtually anything. Just declare a function in your configuration file and add its name into the $SUPPORT variable. See bkp_names and bkp_gitrepos in mkbkp to learn more.
Detects connected screens and set proper video and audio output. It uses xrandr and pulseaudio. I wrote it to easily switch forth and back from my HDMI TV. Change it to fit your needs.
The moin script takes a random song from the specified YouTube playlist and play it. The default player is mpv but you can refine the $PLAYER and $PLAYER_OPTS variables to fit your needs. You may want to wake up in the morning by putting the following in your crontab:
# Plays from monday to friday at 08:00am
0 8 * * 1-5 /path/of/moin <YOUR-API-KEY> <PLAYLIST-ID>
Both the API key and the playlist ID are required. If you don't have a key then make one here. The playlist ID is specified by the "list" parameter of the URL. For example, if the URL of your playlist is the following:
https://www.youtube.com/watch?v=xvIuuKVwY_8&list=RDEMWmz07MSPRGna5rHl5FWPRw&index=40
Then the ID is: RDEMWmz07MSPRGna5rHl5FWPRw
Fetch a random pic from a random blog (of a given list).
This is scrapthumb rewritten from scratch and better. Now the Tumblr API is used so you need an api key.
In a nutshell:
# scrap="$(APIKEY=Your-Api-Key fetchpic)"
# uri="$(echo "$scrap" |cut -d'|' -f2)"
# feh --bg-fill --no-fehbg "$uri"
Put this in your .xinitrc to change the wallapaper each 5 minutes and append
the pic URL and blog name into /tmp/fetchpic.
while : ; do
scrap="$(APIKEY=Your-Api-Key fetchpic)"
uri="$(echo "$scrap" |cut -d' ' -f2)"
echo "$scrap" >> /tmp/fetchpic
feh --bg-fill --no-fehbg "$uri"
sleep 300
done &
Enjoy.
Send a PUSH notification to your smartphone via xdroid API.
$ sendpush -h
sendpush -k <key> -t <title> -c <conten> [-u <uri>]
Install the app and you're done.
Change random wallpapers taken from the web.
Note: I do not use nor mantain wally anymore. Random images rotation is nice
it but cannot always guarantee high quality results thus I decided to use a
curated list of images from a Pexel collection with a script like
this.
$ wally -h
Usage: wally [-h] -f <file>
A configuration file is required to instruct wally about where to take
images, how to filter them, how much wait for the next rotation, etc.
Here is a sample file which support Pexels and wttr:
# wally settings
ENABLED_SERVICES="pexels wttr"
DELAY=300
LOGFILE="/tmp/wally.log"
useresult() {
feh --bg-max --no-fehbg "$1"
}
##
# pexels
# https://www.pexels.com/it-it/api/documentation
##
pexels_apikey="your-api-key"
pexels_opts="auto=compress&cs=tinysrgb&fit=crop&w=1920&h=1080"
pexels_items="space:3000 rain:1000 sexy%20woman:10000 architecture:8000"
pexels() {
nitems="$(obj_items "$pexels_items")"
index="$($(printf "$rand" 1 "$nitems"))"
item="$(obj_items "$pexels_items" "$index")"
query="$(echo -n "$item" |cut -d':' -f1)"
npages="$(echo -n "$item" |cut -d':' -f2)"
page="$($(printf "$rand" 1 "$npages"))"
qs="per_page=1&page=$page&query=$query"
uri="https://api.pexels.com/v1/search?$qs"
json="$(curl -sH "Authorization: $pexels_apikey" "$uri")"
original="$(echo "$json" |sed -n 's/.*"original":"\([^"]*\).*/\1/p')"
log "Pexels $query #$page $original"
[ "$npages" -gt 10000 ] && die "max pages is 10000 (current: $npages)"
[ -z "$original" ] && die "no results"
echo "$original?$pexels_opts"
return 0
}
##
# wttr
# https://wttr.in/:help
##
wttr_lang="it"
wttr_items="_pF.png /moon_pF.png"
wttr() {
nitems="$(obj_items "$wttr_items")"
index="$($(printf "$rand" 1 "$nitems"))"
item="$(obj_items "$wttr_items" "$index")"
uri="https://$wttr_lang.wttr.in${item}"
log "wttr $item $uri"
echo "$uri"
return 0
}
You can add any service you wish. Just create a function to fetch the random
images and add its name into the $ENABLED_SERVICES variable. If you need to
refine how the wallpaper is set you can also define a _use function which
will be called instead of the default useresult().
A non-zero return value tell wally to write an error on the log file
including any eventual output. It also prevent the _use() function to be
called. The die() function may be used for convenience (see below).
Actually, your function may produce any output (not necessarly an URL or a
local filename) and inside _use() you may do anything you want without need
to manage wallpapers at all.
For instance, here is service to produce random numbers:
rnum() {
n="$(shuf -n1 -i 10000-99999)"
# $n == 12345 throw an error
[ "$n" -eq 12345 ] && die "got exactly 12345"
}
rnum_use() {
xmessage -center "Random number: $1"
}
A few convenient functions are availables:
- obj_items: count items in a list or return the given one
- log: append the argument to
$LOGFILE - die: print the argument and exit with code 1
- d: print and log the argument
See the wally script itself for details.