Avoid in-band error indicators while designing interfaces. This practice is commonly used by C library functions but is not recommended. One example from the C Standard of a troublesome in-band error indicator is EOF. (See see FIO34-C. Distinguish between characters read from a file and EOF or WEOF). Another problematic use of in-band error indicators from the C Standard involving the size_t and time_t types is described by
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| [Burch 2006] | |
| [ISO/IEC 9899:2011] | Section Subclause 6.3.2, "Other Operands" |
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