posix_ansi_iso_c
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| ====== POSIX / ANSI / ISO C ====== | ====== POSIX / ANSI / ISO C ====== | ||
| - | ===== [[http:// | + | ===== ANSI / ISO C ===== |
| ANSI C / ISO C are standards designed to support an incredibly broad array of different systems and allow compiling legacy code from ages past. We can call this " | ANSI C / ISO C are standards designed to support an incredibly broad array of different systems and allow compiling legacy code from ages past. We can call this " | ||
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| Half of the C standard refers to the language itself, which includes specific guarantees about what types are available, what syntax you can use, et cetera. These guarantees are sometimes too broad to work with comfortably. For example, in standard C, it is guaranteed that at least the following types exist: | Half of the C standard refers to the language itself, which includes specific guarantees about what types are available, what syntax you can use, et cetera. These guarantees are sometimes too broad to work with comfortably. For example, in standard C, it is guaranteed that at least the following types exist: | ||
| - | | + | |
| - | * int, which represents at least -32767..+32767 | + | |
| - | * long int, which represents at least -2147483647..+2147483647 | + | |
| Each type in the list must be wider than the last, but there is a lot of leeway for systems to choose different sizes. For example, on a DSP or an old supercomputer all of the types might be exactly the same size. There is also no guarantee that a byte has 8 bits (maybe it has more than 8 bits). | Each type in the list must be wider than the last, but there is a lot of leeway for systems to choose different sizes. For example, on a DSP or an old supercomputer all of the types might be exactly the same size. There is also no guarantee that a byte has 8 bits (maybe it has more than 8 bits). | ||
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| There are several versions of standard C. The most common ones are C89/C90, C99, and C11. It is not uncommon to find systems which only support C90 (for example, MSVC). | There are several versions of standard C. The most common ones are C89/C90, C99, and C11. It is not uncommon to find systems which only support C90 (for example, MSVC). | ||
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| ===== POSIX ===== | ===== POSIX ===== | ||
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| There are several versions of POSIX. | There are several versions of POSIX. | ||
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| ===== GLibc ===== | ===== GLibc ===== | ||
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| Programs that use GLibc extensions are not generally portable, although certain extensions are also available on BSD systems. | Programs that use GLibc extensions are not generally portable, although certain extensions are also available on BSD systems. | ||
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| ===== Win32 ===== | ===== Win32 ===== | ||
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| Programs written for Win32 will generally only run on Windows and possibly WINE. | Programs written for Win32 will generally only run on Windows and possibly WINE. | ||
| - | ===== MFC ===== | + | [[http:// |
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| + | ==== MFC ==== | ||
| MFC is a library provided by Microsoft which makes it easier to write Win32 applications. It is effectively obsolete and should not be used for new projects. MFC is not standardized and there is only one implementation. | MFC is a library provided by Microsoft which makes it easier to write Win32 applications. It is effectively obsolete and should not be used for new projects. MFC is not standardized and there is only one implementation. | ||
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| + | [[http:// | ||
| Source: [[https:// | Source: [[https:// | ||
posix_ansi_iso_c.1715641885.txt.gz · Last modified: 2024-05-13 by hanez