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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)

Check Out this Related Man Page

UNW_INIT_LOCAL(3)					       Programming Library						 UNW_INIT_LOCAL(3)

NAME

       unw_init_local -- initialize cursor for local unwinding

SYNOPSIS

       #include <libunwind.h>

       int unw_init_local(unw_cursor_t *c, unw_context_t *ctxt);

DESCRIPTION

       The  unw_init_local()  routine  initializes the unwind cursor pointed to by c with the machine-state in the context structure pointed to by
       ctxt.  As such, the machine-state pointed to by ctxt identifies the initial stack frame at which unwinding starts. The  machine-state  must
       remain valid for the duration for which the cursor c is in use.

       The  unw_init_local()  routine can be used only for unwinding in the address space of the current process (i.e., for local unwinding).  For
       all other cases, unw_init_remote() must be used instead.  From a behavioral point of view, the call:

	   ret = unw_init_local(&cursor, &ucontext);

       is equivalent to:

	   ret = unw_init_remote(&cursor, unw_local_addr_space,
				 &ucontext);

       However, unwind performance may be better when using unw_init_local().  Also, unw_init_local() is available even  when  UNW_LOCAL_ONLY  has
       been defined before including <libunwind.h>, whereas unw_init_remote() is not.

RETURN VALUE

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

THREAD AND SIGNAL SAFETY

       unw_init_local() is thread-safe as well as safe to use from a signal handler.

ERRORS

       UNW_EINVAL
	       unw_init_local()  was  called  in  a  version of libunwind which supports remote unwinding only (this normally happens when calling
	      unw_init_local() for a cross-platform version of libunwind).

       UNW_EUNSPEC
	       An unspecified error occurred.

       UNW_EBADREG
	       A register needed by unw_init_local() wasn't accessible.

SEE ALSO

       libunwind(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_INIT_LOCAL(3)
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