compiler/stdc/background.c

   1 /*
   2     Copyright © 2013, The AROS Development Team. All rights reserved.
   3
   4     This file is there to provide a background section in the Autodocs
   5     for the stdc.library
   6 */
   7
   8 /*******************************************************************************
   9
  10     NAME
  11         --background_C99--
  12
  13     NOTES
  14         On AROS standardized C interfaces are implemented with a few shared
  15         libraries. A distinction is made between a standard ANSI-C/ISO-C
  16         part and a POSIX emulation layer.
  17         Here the ANSI-C/ISO-C part is documented.
  18
  19         The ANSI-C/ISO-C part is implemented by the stdc.library and the
  20         stdcio.library shared libraries. The former implements the part that
  21         only depends on exec.library; the latter the parts that depends on
  22         other libraries like dos.library and contains mostly I/O related
  23         functions.
  24         Currently both libraries are disk based but the plan is in the future
  25         put stdc.library in ROM and be initialized right after exec so that
  26         all modules, also those in ROM can use it. stdcio.library will likely
  27         stay disk based.
  28         Purpose of these libraries is to provide a base implementation that
  29         can be used by compilers. Compilers are free to override functions
  30         with their own implementation.
  31
  32         The reference used for the developing the two libraries is the ISO/IEC
  33         standard document ISO/IEC 9899:1999 also known as C99. Not all functions
  34         are implemented but for each function defined in the standard a place
  35         in the library is reserved. The order of the functions in the library
  36         lookup table is based on the order that they are defined in the standard
  37         document.
  38
  39         Not all functions are implemented. Not implemented functions either
  40         are not available in the library at all or just a stub function is
  41         provided. The latter can be used to get programs running without having
  42         a proper implementation of a function. Of course target should be to
  43         have in the end all functions implemented.
  44         Consult the include files and the autodocs to see which functions are
  45         not (fully) implemented.
  46
  47         The include files provided for the C99 code implement a proper
  48         separation of the include files. The includes should only define the
  49         prototypes as defined by the standard. This means includes like
  50         proto/stdc.h or proto/stdcio.h should not be included in the standard
  51         C99 include files. Developers improving or extending these libraries
  52         should keep this in mind.
  53
  54         In order to use the stdc.library programs need to properly initialize
  55         the library using the __stdc_progam_startup() and __stdc_program_end()
  56         functions. It is assumed that this is taken care of by the startup
  57         code provided by the compiler.
  58
  59     SEE ALSO
  60         posixc.library/--background_posixc--
  61
  62 *******************************************************************************/
  63
  64
  65 /*******************************************************************************
  66
  67     NAME
  68         --background_locale--
  69
  70     NOTES
  71         Currently no real locale support is provided by stdc.library. All locale
  72         related functions have a minimal implementation assuming only a "C"
  73         locale.
  74         Implementing proper locale support will need careful development to have
  75         a consistent integration with locale.library. People with ideas can
  76         always post on the AROS development mailing list.
  77
  78     SEE ALSO
  79         locale.h, --background_wchar-- --background_c99--
  80
  81 *******************************************************************************/
  82
  83
  84 /*******************************************************************************
  85
  86     NAME
  87         --background_wchar--
  88
  89     NOTES
  90         wchar.h/wctype.h is not implemented by stdc.library. It is left to
  91         the compiler to provide their implementation of wchar support.
  92         No system functions should thus at the moment use wchar as
  93         implementation is compiler dependent.
  94
  95     SEE ALSO
  96         --background_locale-- --background_c99--
  97
  98 *******************************************************************************/
  99
 100
 101 /*******************************************************************************
 102
 103     NAME
 104         --background_string--
 105
 106     NOTES
 107         Contrary to the other include files; almost all string functions are
 108         made part of stdc.library include the POSIX and the SAS/C ones.
 109         These string functions are most of the small and don't depend on other
 110         code. Doing it this way avoids having code that only uses non C99 string
 111         functions having a dependency on posixc.library.
 112
 113     SEE ALSO
 114         --background_locale-- --background_c99--
 115
 116 *******************************************************************************/