A Command-line Arguments are passed after the name of a program in command-line operating systems like DOS or Linux and are passed into the program from the operating system. Shell scripts also accept command line arguments similar to nix commands. Command line arguments are useful for passing input to script at runtime which has...
Similar to for loop, while loop is also entry restricted loop. It means condition is checked before executing while loop. Mostly it also can do all the works which for loop can do but in uses it has own benefit of use in programming. Syntax: while [ condition ] do // programme to execute...
Loops are very useful for doing repetitive tasks for any programming language. For loops are also available for bash scripting. In this article we will learn about uses of for loops with useful examples. Syntax: for VARIABLE in PARAM1 PARAM2 PARAM3 do // commands to execute done In above syntax PARAM1, PARAM2 and PARAM3...
Sample Script STR=”Sarah;Lisa;Jack;Rahul;Johnson” IFS=’;’ read -ra NAMES
Command SNAME=$(basename “$(test -L “$0” && readlink “$0” || echo “$0″)”) While running a bash script using Linux terminal the script name can also passed as argument at $0. but if we are using full path of script to execute, it will show full path as results when print value of $0. So use...
Command: str3=”$str1 $str2″ The above example command will concatenate values of str1 and str2 stings and store it in third variable str3. Make sure there should not be any space before or after the assignment ( = ) operator. Example 1: It is simply write two or more strings variable one after one for...
Command: if [ “$str1” == “$str2” ] Example: Take input of two string in a script and compare if both are same or not, using if statement. Create a bash script using below content and execute. It will prompt for two strings from user and check if both string are same or not. #!/bin/bash...
Command: while true;do echo “Press CTRL+C to Exit”; done Example 1: Some times we are required to execute some commands or processes continuously until stop it forcefully or conditionally. The following example of while loop will run continuously until stopped forcefully using ctrl + c. while true do echo "Press CTRL+C to Exit" done...
Command: echo -e “\\e[0;41mBackground in Red Color\\e[0m” The Above commands are using to set background color of output on Linux bash shell. In The output of above command background will be in red color. There are many other colors available which you can use defined as below. Just replace “0;41” with other color values...
# echo -e “e[0;31mText in Red Colore[0m” The Above commands are showing to set foreground ( Text ) color of output on Linux bash shell. The output of above command will be in red color. There are many other colors available which you can use defined as below. Just replace “0;31” with other color...