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) | |
| (C11) | issues a compile-time diagnostic if the value of a constant expression is false (function macro) | 

