Tag Archives: bash

bash scripts

Bash script for GitHub to fix bad commit branch.

One mistake is to have changed in the [master] branch instead of [mymain]. This can be fixed with this bash script:

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# check the branch that you committed to by accident, in this case, is master
git checkout master
 
# reset the branch back one commit
git reset --soft HEAD^
 
# use stash to record the current state of the working directory
git stash
 
# checkout the branch it should be in, in this case, is mymain
git checkout mymain
 
# apply the stash
git stash apply
 
# commit the changes
git commit -am "main commit"
 
# then push the changes to our main branch
git push origin mymain
 
# checkout the original branch, in this case, is master
git checkout master
 
# the last step is to force push the commit deletion to the original branch.
git push --force origin master

Hope this help’s !!

Bash: Get IP and IPv6 address and interfaces.

First use this commands to see your IP and IPv6 address and interfaces.

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/sbin/ifconfig $1 | grep "inet\|inet6" | awk -F' ' '{print $2}' | awk '{print $1}'
/sbin/ifconfig |grep -B1 "inet\|inet6" |awk '{ if ( $1 == "inet" || $1 == "inet6" )
{ print "  ",$2 } else if ( $1 != "inet" && $1 != "inet6" ) { print $1 } }'

Now if you want to use this every day, just open your .bashrc file from your home folder. Add these functions to the .bashrc file:

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# User specific aliases and functions
 
function getip { /sbin/ifconfig $1 | grep "inet\|inet6" |
awk -F' ' '{print $2}' | awk '{print $1}'; }
 
function getips { /sbin/ifconfig |grep -B1 "inet\|inet6" |
awk '{ if ( $1 == "inet" || $1 == "inet6" ) { print "  ",$2 }
else if ( $1 != "inet" && $1 != "inet6" ) { print $1 } }'; }

Now open a new terminal shell and use it:

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$getip
$getips

Linux .bashrc to extract many archives

This is just a new function to uncompressing many files like: .tar.bz2,.tar.gz,.bz2,.rar,.gz,.tar,.tbz2,.tgz,.zip,.Z,.7z Open .bashrc file from home/user folder. With your text editor and add the next function on the end of the file.

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function unarchive()      
{
    if [ -f $1 ] ; then
        case $1 in
            *.tar.bz2)   tar xvjf $1     ;;
            *.tar.gz)    tar xvzf $1     ;;
            *.bz2)       bunzip2 $1      ;;
            *.rar)       unrar x $1      ;;
            *.gz)        gunzip $1       ;;
            *.tar)       tar xvf $1      ;;
            *.tbz2)      tar xvjf $1     ;;
            *.tgz)       tar xvzf $1     ;;
            *.zip)       unzip $1        ;;
            *.Z)         uncompress $1   ;;
            *.7z)        7z x $1         ;;
            *)           echo "'$1' cannot be extracted via >unarchive<" ;;
        esac
    else
        echo "'$1' is not a valid file!"
    fi
}

Open a new terminal. This will work with the new function from .bashrc.

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$ unarchive glib-2.30.2.tar.bz2

Simple bash script to create folders, files and images .

How to create a series of directories using a standard format.

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printf "image%01d\n" $(seq 0 3) | xargs -I{} mkdir {}

Let’s see the result :

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$ ls image*
image0/ image1/ image2/ image3/

Delete all this folder is easy, just use this command:

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printf "image%01d\n" $(seq 0 3) | xargs -I{} rm {} -f -r

How to create a series of text files using a standard format.

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printf "text%01d\n" $(seq 0 3) | xargs -I{} touch {}.txt

Let’s see the result :

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$ ls text*.txt
text0.txt  text1.txt  text2.txt  text3.txt
 

How to create a series of random… Read More »

Simple bash script : scan and convert the image in JPG format.

I use to Linux commands: scanimage and convert. We can see the script below:

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#!/bin/bash
args=("$@")
echo ${args[0]}
exec `scanimage --mode=Color --format=PNM > ${args[0]}.raw ;
convert ${args[0]}.raw ${args[0]}.jpg;
rm ${args[0]}.raw;`

Write the script in a text file. Named the script with this name scan.sh. Run this :

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$sh scan.sh firstscan

The output will be:

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firstscan.jpg

You can use any name for the output. As we see in this example I used firstscan.

Parsing files and rename …

Sometimes you have to rename files. This can be tiring when we do it manually. Command sed may be helpful in this case. I’ll take a simple example. I will create a working directory called work. We have to create files with the command:

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for (( i=1; i<10; i++ )); do echo data$i > data[$i]x[$i].txt;done
 

The result should be :

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$ ls
data[1]x[1].txt  data[3]x[3].txt  data[5]x[5].txt  data[7]x[7].txt  data[9]x[9].txt
data[2]x[2].txt  data[4]x[4].txt  data[6]x[6].txt  data[8]x[8].txt
 

Try these commands to… Read More »