| 1 | /* $NetBSD: featuretest.h,v 1.10 2013/04/26 18:29:06 christos Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Written by Klaus Klein <kleink@NetBSD.org>, February 2, 1998. |
| 5 | * Public domain. |
| 6 | * |
| 7 | * NOTE: Do not protect this header against multiple inclusion. Doing |
| 8 | * so can have subtle side-effects due to header file inclusion order |
| 9 | * and testing of e.g. _POSIX_SOURCE vs. _POSIX_C_SOURCE. Instead, |
| 10 | * protect each CPP macro that we want to supply. |
| 11 | */ |
| 12 | |
| 13 | /* |
| 14 | * Feature-test macros are defined by several standards, and allow an |
| 15 | * application to specify what symbols they want the system headers to |
| 16 | * expose, and hence what standard they want them to conform to. |
| 17 | * There are two classes of feature-test macros. The first class |
| 18 | * specify complete standards, and if one of these is defined, header |
| 19 | * files will try to conform to the relevant standard. They are: |
| 20 | * |
| 21 | * ANSI macros: |
| 22 | * _ANSI_SOURCE ANSI C89 |
| 23 | * |
| 24 | * POSIX macros: |
| 25 | * _POSIX_SOURCE == 1 IEEE Std 1003.1 (version?) |
| 26 | * _POSIX_C_SOURCE == 1 IEEE Std 1003.1-1990 |
| 27 | * _POSIX_C_SOURCE == 2 IEEE Std 1003.2-1992 |
| 28 | * _POSIX_C_SOURCE == 199309L IEEE Std 1003.1b-1993 |
| 29 | * _POSIX_C_SOURCE == 199506L ISO/IEC 9945-1:1996 |
| 30 | * _POSIX_C_SOURCE == 200112L IEEE Std 1003.1-2001 |
| 31 | * _POSIX_C_SOURCE == 200809L IEEE Std 1003.1-2008 |
| 32 | * |
| 33 | * X/Open macros: |
| 34 | * _XOPEN_SOURCE System Interfaces and Headers, Issue 4, Ver 2 |
| 35 | * _XOPEN_SOURCE_EXTENDED == 1 XSH4.2 UNIX extensions |
| 36 | * _XOPEN_SOURCE == 500 System Interfaces and Headers, Issue 5 |
| 37 | * _XOPEN_SOURCE == 520 Networking Services (XNS), Issue 5.2 |
| 38 | * _XOPEN_SOURCE == 600 IEEE Std 1003.1-2001, XSI option |
| 39 | * _XOPEN_SOURCE == 700 IEEE Std 1003.1-2008, XSI option |
| 40 | * |
| 41 | * NetBSD macros: |
| 42 | * _NETBSD_SOURCE == 1 Make all NetBSD features available. |
| 43 | * |
| 44 | * If more than one of these "major" feature-test macros is defined, |
| 45 | * then the set of facilities provided (and namespace used) is the |
| 46 | * union of that specified by the relevant standards, and in case of |
| 47 | * conflict, the earlier standard in the above list has precedence (so |
| 48 | * if both _POSIX_C_SOURCE and _NETBSD_SOURCE are defined, the version |
| 49 | * of rename() that's used is the POSIX one). If none of the "major" |
| 50 | * feature-test macros is defined, _NETBSD_SOURCE is assumed. |
| 51 | * |
| 52 | * There are also "minor" feature-test macros, which enable extra |
| 53 | * functionality in addition to some base standard. They should be |
| 54 | * defined along with one of the "major" macros. The "minor" macros |
| 55 | * are: |
| 56 | * |
| 57 | * _REENTRANT |
| 58 | * _ISOC99_SOURCE |
| 59 | * _ISOC11_SOURCE |
| 60 | * _LARGEFILE_SOURCE Large File Support |
| 61 | * <http://ftp.sas.com/standards/large.file/x_open.20Mar96.html> |
| 62 | */ |
| 63 | |
| 64 | #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE) |
| 65 | #define _POSIX_C_SOURCE 1L |
| 66 | #endif |
| 67 | |
| 68 | #if !defined(_ANSI_SOURCE) && !defined(_POSIX_C_SOURCE) && \ |
| 69 | !defined(_XOPEN_SOURCE) && !defined(_NETBSD_SOURCE) |
| 70 | #define _NETBSD_SOURCE 1 |
| 71 | #endif |
| 72 | |
| 73 | #if ((_POSIX_C_SOURCE - 0) >= 199506L || (_XOPEN_SOURCE - 0) >= 500) && \ |
| 74 | !defined(_REENTRANT) |
| 75 | #define _REENTRANT |
| 76 | #endif |
| 77 | |