Describes the ld_info data type and loader entry points.
#include <sys/ldr.h
The /usr/include/sys/ldr.h header file contains declarations of the ld_info structure and the system loader entry points available to processes and kernel extensions.
The ld_info structure describes an XCOFF object file in the context of either tracing a process (with the ptrace system call) or examining a core file. The ldr.h file can define 2 variants of the ld_info structure, one for describing 32-bit processes (__ld_info32) and one for describing 64-bit processes (__ld_info64). If the __LDINFO_PTRACE32__ symbol is defined, so is the struct __ld_info32 type. If the __LDINFO_PTRACE64__ symbol is defined, so is the struct __ld_info64 type. If the compilation mode is 32-bit and the __LDINFO_PTRACE32__ symbol is defined, the struct __ld_info32 and struct ld_info types are equivalent. If the compilation mode is 64-bit and the __LDINFO_PTRACE64__ symbol is defined, the struct __ld_info64 and struct ld_info types are equivalent.
When using ptrace in a 32-bit program to debug a 64-bit process, define __LDINFO_PTRACE64__. When using ptrace in a 64-bit program to debug a 32-bit process, define __LDINFO_PTRACE32__. (This is not supported in AIX 4.3.)
The types and sizes of these structures' fields depend on whether the compilation mode is 32-bit or 64-bit. The same field names are generated in both structure modes, with the exception that the 64-bit structure has an ldinfo_flags field, which is reserved for future use.
The __ld_info32 and __ld_info64 structures contain the following fields of the indicated sizes and types; when two types are listed, the first is used when the compilation mode is 32-bit and the second is used when the mode is 64-bit:
| Field | Description | __ld_info32 | __ld_info64 | ||
|---|---|---|---|---|---|
| Size | Type(s) | Size | Type(s) | ||
| ldinfo_next | Offset from current entry of next entry, or zero if last entry. | 4 | uint | 4 | uint |
| ldinfo_flags | Reserved for future use. | N/A | N/A | 4 | uint |
| ldinfo_fd | File descriptor returned by ptrace to debugger. | 4 | int | 4 | int |
| ldinfo_fp | File pointer returned by loader to ptrace. | 4 | struct file *, uint | 4 | struct file *, uint |
| ldinfo_core | Offset into core file of object. | 4 | int | 8 | long long, long |
| ldinfo_textorg | Offset to loaded program image, including the XCOFF headers. | 4 | void *, uint | 8 | unsigned long long, void * |
| ldinfo_textsize | Length of loaded program image. | 4 | int | 8 | long long, long |
| ldinfo_dataorg | Start of data. | 4 | void *, uint | 8 | unsigned long long, void * |
| ldinfo_datasize | Size of data. | 4 | int | 8 | long long, long |
| ldinfo_filename | Nul-terminated path name followed by nul-terminated member name; member name is empty if not an archive. | variable | char[2] | variable | char[2] |
The ldr.h header declares the following functions:
int kmod_load(caddr_t path, uint flags, caddr_t libpath, mid_t *kmid); int kmod_unload(mid_t kmid, uint flags); void (*(kmod_entrypt(mid_t kmid, uint flags)))(); int ld_info(int __flags, pid_t __pid, void *__buffer, unsigned int __length); __LOAD_T *load(char *__filenameparm, uint __flags, char *__libpathparm); int loadbind(int __lflags, void *__exporter, void *__importer); int unload(void *__function); int loadquery(int __lflags, void *__buffer, unsigned int __length); __handler_t *__lazySetErrorHandler( __handler_t *fp );
The load, loadbind, loadquery, and unload subroutines.