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What are the arguments for Bash exec builtin?
Options and arguments. The exec builtin command takes the following options and arguments: -a name. Pass the string name as the zeroth argument to command. This option is available in bash versions 4.2 and above. When used, it will execute command, and set the special shell variable $0 to the value name, instead of command.
How to use Bash case statement in scripting?
In scripting, the bash builtincasemakes it easy to have more complex conditional statements without having to nest a bunch of if statements. You can selectively execute a command listor pipeline that corresponds to the first matched pattern.
Which is the builtin command in Bash shell?
Bash exec builtin command. Updated: 05/04/2019 by. On Unix-like operating systems, exec is a builtin command of the Bash shell. It allows you to execute a command that completely replaces the current process.
What happens to the shell when you use exec?
The current shell process is destroyed, and entirely replaced by the command you specify. exec is a critical function of any Unix -like operating system. Traditionally, the only way to create a new process in Unix is to fork it.
How to test if a command succeeded in Bash?
It’s probably the most common command to use in an if, which can lead to the assumption that it’s part of the shell’s syntax. But if you want to test whether a command succeeded or not, use the command itself directly with if, as shown above. For small things that you want to happen if a shell command works, you can use the && construct:
How to run multiple commands in one line in Bash?
&& executes the right-hand command of && only if the previous one succeeded. || executes the right-hand command of || only it the previous one failed. ; executes the right-hand command of ; always regardless whether the previous command succeeded or failed. Unless set -e was previously invoked, which causes bash to fail on an error.