unw_get_proc_name(3) [debian man page]

UNW_GET_PROC_NAME(3)					       Programming Library					      UNW_GET_PROC_NAME(3)

NAME

       unw_get_proc_name -- get name of current procedure

SYNOPSIS

       #include <libunwind.h>

       int unw_get_proc_name(unw_cursor_t *cp, char *bufp, size_t len, unw_word_t *offp);

DESCRIPTION

       The  unw_get_proc_name()  routine returns the name of the procedure that created the stack frame identified by argument cp.  The bufp argu-
       ment is a pointer to a character buffer that is at least len bytes long. This buffer is used to return the name of the procedure. The  offp
       argument  is  a	pointer to a word that is used to return the byte-offset of the instruction-pointer saved in the stack frame identified by
       cp, relative to the start of the procedure. For example, if procedure foo() starts at address 0x40003000, then invoking unw_get_proc_name()
       on  a stack frame with an instruction-pointer value of 0x40003080 would return a value of 0x80 in the word pointed to by offp (assuming the
       procedure is at least 0x80 bytes long).

       Note that on some platforms there is no reliable way to distinguish between procedure names and ordinary  labels.  Furthermore,	if  symbol
       information  has  been  stripped  from  a  program, procedure names may be completely unavailable or may be limited to those exported via a
       dynamic symbol table. In such cases, unw_get_proc_name() may return the name of a label or a preceeding (nearby) procedure.   However,  the
       offset  returned through offp is always relative to the returned name, which ensures that the value (address) of the returned name plus the
       returned offset will always be equal to the instruction-pointer of the stack frame identified by cp.

RETURN VALUE

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

THREAD AND SIGNAL SAFETY

       unw_get_proc_name() is thread-safe. If cursor cp is in the local address-space, 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 name of the procedure.

       UNW_ENOMME
	       The procedure name is too long to fit in the buffer provided. A truncated version of the name has been returned.

       In addition, unw_get_proc_name() may return any error returned by the access_mem() call-back (see unw_create_addr_space(3)).

SEE ALSO

       libunwind(3), unw_get_proc_info(3)

AUTHOR

       David Mosberger-Tang
       Email: dmosberger@gmail.com
       WWW: http://www.nongnu.org/libunwind/.

Programming Library						  16 August 2007					      UNW_GET_PROC_NAME(3)

UNW_GET_PROC_INFO_BY_IP(3)				       Programming Library					UNW_GET_PROC_INFO_BY_IP(3)

NAME

       unw_get_proc_info_by_ip -- get procedure info by IP

SYNOPSIS

       #include <libunwind.h>

       int unw_get_proc_info_by_ip(unw_addr_space_t as, unw_word_t ip, unw_proc_info_t *pip, void *arg);

DESCRIPTION

       The  unw_get_proc_info_by_ip() routine returns the same kind of auxiliary information about a procedure as unw_get_proc_info(), except that
       the info is looked up by instruction-pointer (IP) instead of a cursor. This is more flexible because it is possible to look up the info for
       an  arbitrary  procedure, even if it is not part of the current call-chain. However, since it is more flexible, it also tends to run slower
       (and often much slower) than unw_get_proc_info().

       The routine expects the followins 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
       procedure info should be looked up and pip is a pointer to a structure of type unw_proc_info_t which is used to return the  info.   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.

       Note  that  for	the  purposes of libunwind, the code of a procedure is assumed to occupy a single, contiguous range of addresses. For this
       reason, it is alwas possible to describe the extent of a procedure with the start_ip and end_ip members. If a  single  function/routine	is
       split into multiple, discontiguous pieces, libunwind will treat each piece as a separate procedure.

RETURN VALUE

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

THREAD AND SIGNAL SAFETY

       unw_get_proc_info()  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 locate unwind-info for the procedure.

       UNW_EBADVERSION
	       The unwind-info for the procedure has version or format that is not understood by libunwind.

       In addition, unw_get_proc_info() may return any error returned by the access_mem() call-back (see unw_create_addr_space(3)).

SEE ALSO

       libunwind(3), unw_create_addr_space(3), unw_get_proc_name(3), unw_get_proc_info(3), unw_init_remote(3)

AUTHOR

       David Mosberger-Tang
       Email: dmosberger@gmail.com
       WWW: http://www.nongnu.org/libunwind/.

Programming Library						  16 August 2007					UNW_GET_PROC_INFO_BY_IP(3)