UNIX & Linux Convert strings to command execution

This article applies to the following topics:

1. Unix & Linux Convert string to command

2. UNIX & Linux Convert strings to command execution

3. How to convert a string into a command in a Linux sh script

Answer:

Use the eval command in a shell script (this command is Bash's built-in command, which is used when Bash's built-in commands view help with man Eval), not exec.

Grammar:

Eval parameters

Parameters can be strings for a set of commands, such as "eval yum install Dstat–y", if you do not add parameters directly to Eval can also, return error code is still 0 (successful execution), but meaningless.

Why not exec?

Because exec exits the current shell script automatically after execution, all rows after exec are ignored.

Why does exec automatically quit?

exec does not start a new shell, but instead replaces the current shell (the currently running script or login session) with the command that follows it.

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