/*** *mterrno.c - provide function versions of errno & _doserrno for LIBC.LIB * * Copyright (c) 1994-2001, Microsoft Corporation. All rights reserved. * *Purpose: * Sometimes users want to compile code (such as for use in a library) * for both single-thread and multi-thread applications. Currently the * one major stumbling block to doing this is the fact that errno & * _doserrno are defined in different ways in LIBC.LIB and LIBCMT.LIB. * Code that should otherwise be usable with both LIBC.LIB and LIBCMT.LIB * but which accesses errno and/or _doserrno is not usable with both. * By providing the function versions of errno & _doserrno in LIBC.LIB, * users can compile their code for both LIBCMT.LIB and LIBC.LIB. * Note that this does not magically make single-thread code safe in a * multi-threaded environment, it merely makes it easier to use the * same code with LIBC.LIB and LIBCMT.LIB. * *Revision History: * 03-26-94 SKS Original version. * *******************************************************************************/ #ifndef _MT /* Get the definitions of the function versions of errno/_doserrno */ #define _MT #include #undef _MT /* undo the macros that convert the variable names to function calls */ #undef errno #undef _doserrno /* declare the variables - must match the definitions in */ extern int errno; /* XENIX style error number */ extern unsigned long _doserrno; /* OS system error value */ /*** *int * _errno() - return pointer to thread's errno *unsigned long * __doserrno() - return pointer to thread's _doserrno * *Purpose: * _errno() returns a pointer to the global variable errno * __doserrno returns a pointer to the global variable _doserrno * *Entry: * None. * *Exit: * See above. * *Exceptions: * *******************************************************************************/ int * __cdecl _errno( void ) { return & errno; } unsigned long * __cdecl __doserrno( void ) { return & _doserrno; } #endif /* !_MT */