Errno

Decodes the errno value from a raw syscall result.

Module: Linux

Signature

func Errno(result: int64) -> int64;

Parameters

Name	Type	Description
result	int64	Raw syscall return value.

Returns

int64 — the positive errno value when result is between -4095 and -1, or 0 when the value does not encode an error.

Description

Errno does not read or modify a global or thread-local errno variable. It only decodes the supplied kernel return value.

TIP

Call IsError when you need to distinguish success from failure. Errno(result) == 0 means the input was not an encoded syscall error.

Example

import Linux::{ Errno, IsError, Write };

let result = Write(fd, data, length);
if IsError(result) {
    let errorNumber = Errno(result);
}

See also

• IsError — test a raw result