- Used to indicate the current status of a program, such as success, failure, error, etc.
- Return values are typically used to indicate the success of a function.
- Used to indicate the status of the file opening, such as opening successfully, opening failed, etc.
- This is used to indicate the status of network communication, such as successful or disconnected connections.
- Used to indicate the execution status of a process, such as running, stopped, etc.
- Used to indicate the execution status of a thread, such as running or finished.
- This is used to indicate error codes from the operating system, such as file not found, insufficient permissions, and so on.
- Used to indicate the results of database operations, such as successful queries or failed insertions.
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