Palautuskoodi

Palautuskoodi, often translated as "return code" or "exit code," is a numerical value that a program or command returns to the operating system upon its completion. This code serves as a simple indicator of how the program executed. By convention, a return code of zero signifies successful execution, while any non-zero value typically indicates that an error or some other abnormal condition occurred.

The specific meaning of non-zero return codes can vary widely depending on the program. Some programs use a standardized set of error codes, while others define their own unique codes to represent different types of failures. For example, a file not found error might have a specific return code, while a permission denied error might have another. Users and system administrators can check these return codes to diagnose problems or to automate tasks based on program outcomes.

In scripting and shell environments, return codes are frequently used in conditional logic. A script might check the return code of a preceding command before proceeding with further actions. This allows for the creation of robust scripts that can handle errors gracefully and adapt their behavior accordingly. Understanding and utilizing return codes is a fundamental aspect of efficient command-line usage and system administration.