am a new to shell scripting. How do I check for NULL value in a Linux or Unix shell scripts?
y shell script depends upon user input. How do I find out if a variable called $_JAIL path is empty under a Linux / Apple OS X / Unix like operating systems? Can you tell me command on bash shell to find out if a variable is empty?
ow do I check in GNU/Bash if a shell is running in interactive mode or not while writing shell scripts?
I‘m using Debian Linux as my development workstation. I would like to search a directory called ~/projects/ recursively for “foo” word only for *.txt files. How do I search all text files in ~/projects/ for “foo” word using grep command?
How do I determine if a function called foo() is already defined in a bash script or not? If a function called foo() is defined just call it or show an error message?
ow can you test if a file is writable under UNIX / Linux bash shell scripting and programming language?
How do I append additional text a variable? For e.g., I’ve a vech set as follows:
I’d like to add (append) “Bus” word to $vevh under UNIX scripting using bash?