Bash

I still remember, at my previous job, one day I had to copy around 2500 … Read More

The sleep command in bash is used to insert delays and pauses into the execution of the instructions to control the flow of the script.

To if a string is empty or not in bash -z string comparison operator is used. It returns true if the string is empty.

To extract the filename in bash, use the file paths with the basename command. Alternatively, awk, sed, and parameter extension methods can also be used.

The \n can be used with the echo command to add a new line in the bash scripting with the use of the “e” option of the echo command with the \n notation.

To split a string on a delimiter in bash programming, users can use the IFS methods, the cut command, the tr command, or the awk command.

JSON scripting is not supported in shell scripting, but with the help of the jq command, it is made possible to the best extent. The curl command also helps.

In Bash, the “<<<” operator means “here strings.” It allows users to pass a string as the standard input to a command via the “command <<< string” syntax.

To restart the Bash shell without restarting the terminal application, type the “exec bash” command that replaces the current process with the Bash shell.

To check if a variable exists in an if statement in bash scripting, the -v flag is used. However, checking a variable for a null or zero value -z flag is used.

In Bash, the regular expression ‘^[0-9]+$’ matches a string that contains only one or more digits (0-9) and no other characters.

In Bash, the main difference between $@ and $* is that “$@” preserves the individual arguments as separate words, while other preserves them as a single string.

In Bash, the “eval” command evaluates its arguments as a shell script including “commands”, “variables”, “arithmetic expressions”, and “strings”.

To implement the for each line operation on a file, the for loop is used in Bash scripting. This can be used to read each line of a file.

Linux offers the “chmod” command with the “x” permission to make a Bash script executable. Also, you can set permission using the octal numbers.

Linux offers the “history” command with the “c” option to clear the bash history. It removes all the records of previously entered commands in the terminal.

In Bash, the until loop iterates the code until the specified condition is met. Using the until loop, users can modify conditions according to requirements.

To read a file line by line in a bash script, we can use the read command with the while loop or the cat command with the for a loop.