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glibc  2.9
dlfcn.h
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00001 /* System dependent definitions for run-time dynamic loading.
00002    Copyright (C) 1996, 1997, 1999, 2000, 2001, 2004
00003        Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005 
00006    The GNU C Library is free software; you can redistribute it and/or
00007    modify it under the terms of the GNU Lesser General Public
00008    License as published by the Free Software Foundation; either
00009    version 2.1 of the License, or (at your option) any later version.
00010 
00011    The GNU C Library is distributed in the hope that it will be useful,
00012    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014    Lesser General Public License for more details.
00015 
00016    You should have received a copy of the GNU Lesser General Public
00017    License along with the GNU C Library; if not, write to the Free
00018    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00019    02111-1307 USA.  */
00020 
00021 #ifndef _DLFCN_H
00022 # error "Never use <bits/dlfcn.h> directly; include <dlfcn.h> instead."
00023 #endif
00024 
00025 /* The MODE argument to `dlopen' contains one of the following: */
00026 #define RTLD_LAZY    0x0001 /* Lazy function call binding.  */
00027 #define RTLD_NOW     0x0002 /* Immediate function call binding.  */
00028 #define RTLD_BINDING_MASK  0x3     /* Mask of binding time value.  */
00029 #define RTLD_NOLOAD  0x00008       /* Do not load the object.  */
00030 #define RTLD_DEEPBIND       0x00010       /* Use deep binding.  */
00031 
00032 /* If the following bit is set in the MODE argument to `dlopen',
00033    the symbols of the loaded object and its dependencies are made
00034    visible as if the object were linked directly into the program.  */
00035 #define RTLD_GLOBAL  0x0004
00036 
00037 /* Unix98 demands the following flag which is the inverse to RTLD_GLOBAL.
00038    The implementation does this by default and so we can define the
00039    value to zero.  */
00040 #define RTLD_LOCAL      0
00041 
00042 /* Do not delete object when closed.  */
00043 #define RTLD_NODELETE       0x01000
00044 
00045 #ifdef __USE_GNU
00046 /* To support profiling of shared objects it is a good idea to call
00047    the function found using `dlsym' using the following macro since
00048    these calls do not use the PLT.  But this would mean the dynamic
00049    loader has no chance to find out when the function is called.  The
00050    macro applies the necessary magic so that profiling is possible.
00051    Rewrite
00052        foo = (*fctp) (arg1, arg2);
00053    into
00054         foo = DL_CALL_FCT (fctp, (arg1, arg2));
00055 */
00056 # define DL_CALL_FCT(fctp, args) \
00057   (_dl_mcount_wrapper_check ((void *) (fctp)), (*(fctp)) args)
00058 
00059 __BEGIN_DECLS
00060 
00061 /* This function calls the profiling functions.  */
00062 extern void _dl_mcount_wrapper_check (void *__selfpc) __THROW;
00063 
00064 __END_DECLS
00065 
00066 #endif