Error handling

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[edit] Types

Defined in header <errno.h>
Defined in header <stdio.h>
errno_t
(C11)
the type of errno value
(typedef)

[edit] Error numbers

Defined in header <errno.h>
macro which expands to POSIX-compatible thread-local error number variable
(macro variable)
macros for standard POSIX-compatible error conditions
(macro constant)

[edit] Assertions

Defined in header <assert.h>
aborts the program if the user-specified condition is not true. May be disabled for release builds
(function macro)
issues a compile-time diagnostic if the value of a constant expression is false
(function macro)