avr-libc  2.0.0
Standard C library for AVR-GCC

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Macros | Variables
<errno.h>: System Errors


#define EDOM   33
#define ERANGE   34


int errno

Detailed Description

#include <errno.h>

Some functions in the library set the global variable errno when an error occurs. The file, <errno.h>, provides symbolic names for various error codes.

Macro Definition Documentation

#define EDOM   33

Domain error.

#define ERANGE   34

Range error.

Variable Documentation

int errno

Error code for last error encountered by library.

The variable errno holds the last error code encountered by a library function. This variable must be cleared by the user prior to calling a library function.

The errno global variable is not safe to use in a threaded or multi-task system. A race condition can occur if a task is interrupted between the call which sets error and when the task examines errno. If another task changes errno during this time, the result will be incorrect for the interrupted task.