debian man page for unw_init_local

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)