#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.
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.