dyld(3) BSD Library Functions Manual dyld(3)NAME
_dyld_image_count, _dyld_get_image_header, _dyld_get_image_vmaddr_slide,
_dyld_get_image_name, _dyld_register_func_for_add_image,
_dyld_register_func_for_remove_image, NSVersionOfRunTimeLibrary,
NSVersionOfLinkTimeLibrary _NSGetExecutablePath
SYNOPSIS
#include <mach-o/dyld.h>
uint32_t
_dyld_image_count(void);
const struct mach_header*
_dyld_get_image_header(uint32_t image_index);
intptr_t
_dyld_get_image_vmaddr_slide(uint32_t image_index);
const char*
_dyld_get_image_name(uint32_t image_index);
void
_dyld_register_func_for_add_image(void (*func)(const struct mach_header* mh, intptr_t vmaddr_slide));
void
_dyld_register_func_for_remove_image(void (*func)(const struct mach_header* mh, intptr_t vmaddr_slide));
int32_t
NSVersionOfRunTimeLibrary(const char* libraryName);
int32_t
NSVersionOfLinkTimeLibrary(const char* libraryName);
int
_NSGetExecutablePath(char* buf, uint32_t* bufsize);
DESCRIPTION
These routines provide additional introspection of dyld beyond that pro‐
vided by dlopen() and dladdr()_dyld_image_count() returns the current number of images mapped in by
dyld. Note that using this count to iterate all images is not thread
safe, because another thread may be adding or removing images during the
iteration.
_dyld_get_image_header() returns a pointer to the mach header of the
image indexed by image_index. If image_index is out of range, NULL is
returned.
_dyld_get_image_vmaddr_slide() returns the virtural memory address slide
amount of the image indexed by image_index. If image_index is out of
range zero is returned.
_dyld_get_image_name() returns the name of the image indexed by
image_index. The C-string continues to be owned by dyld and should not
deleted. If image_index is out of range NULL is returned.
_dyld_register_func_for_add_image() registers the specified function to
be called when a new image is added (a bundle or a dynamic shared
library) to the program. When this function is first registered it is
called for once for each image that is currently part of the process.
_dyld_register_func_for_remove_image() registers the specified function
to be called when an image is removed (a bundle or a dynamic shared
library) from the process.
NSVersionOfRunTimeLibrary() returns the current_version number of the
currently loaded dylib specifed by the libraryName. The libraryName
parameter would be "bar" for /path/libbar.3.dylib and "Foo" for
/path/Foo.framework/Versions/A/Foo. This function returns -1 if no such
library is loaded.
NSVersionOfLinkTimeLibrary() returns the current_version number that the
main executable was linked against at build time. The libraryName param‐
eter would be "bar" for /path/libbar.3.dylib and "Foo" for
/path/Foo.framework/Versions/A/Foo. This function returns -1 if the main
executable did not link against the specified library.
_NSGetExecutablePath() copies the path of the main executable into the
buffer buf. The bufsize parameter should initially be the size of the
buffer. This function returns 0 if the path was successfully copied, and
* bufsize is left unchanged. It returns -1 if the buffer is not large
enough, and * bufsize is set to the size required. Note that
_NSGetExecutablePath() will return "a path" to the executable not a "real
path" to the executable. That is, the path may be a symbolic link and
not the real file. With deep directories the total bufsize needed could
be more than MAXPATHLEN.
SEE ALSOdlopen(3)dladdr(3)dyld(1) http://developer.apple.com/documenta‐
tion/DeveloperTools/Conceptual/MachOTopics/index.html
November 29, 2010