UNW\_GET\_ELF\_FILENAME\_BY\_IP(3libunwind)

NAME
unw_get_elf_filename_by_ip -- get backing elf filename by instruction pointer

SYNOPSIS

#include <libunwind.h>

int unw_get_elf_filename_by_ip(unw_addr_space_t as, unw_word_t ip, char *bufp, size_t len, unw_word_t *offp, void *arg);

DESCRIPTION

The unw_get_elf_filename_by_ip() routine returns the backing elf filename of a instruction pointer just like unw_get_elf_filename(), except that the name is looked up by instruction pointer (IP) instead of a cursor.

The routine expects the following arguments: as is the address-space in which the instruction pointer should be looked up. For a look-up in the local address-space, unw_local_addr_space can be passed for this argument. Argument ip is the instruction-pointer for which the elf filename should be looked up. The bufp argument is a pointer to a character buffer that is at least len bytes long. This buffer is used to return the elf filename. The offp argument is a pointer to a word that is used to return the byte offset of the instruction-pointer relative to the start of the elf filename. Lastly, arg is the address space argument that should be used when accessing the address space. It has the same purpose as the argument of the same name for unw_init_remote(). When accessing the local address space (first argument is unw_local_addr_space), NULL must be passed for this argument.

RETURN VALUE

On successful completion, unw_get_elf_filename_by_ip() returns 0. Otherwise the negative value of one of the error codes below is returned.

THREAD AND SIGNAL SAFETY

unw_get_elf_filename_by_ip() is thread safe. If the local address-space is passed in argument as, this routine is also safe to use from a signal handler.

ERRORS

UNW_EUNSPEC
     An unspecified error occurred.

UNW_ENOINFO
     Libunwind was unable to determine the elf filename of the instruction pointer.

UNW_ENOMEM
     The elf filename is too long to fit in the buffer provided. A truncated version of the name has been returned.

SEE ALSO

libunwind(3libunwind), unw_get_elf_filename(3libunwind), unw_create_addr_space(3libunwind), unw_init_remote(3libunwind)

AUTHOR

Xiang Lin
Email: myd.xia@gmail.com