plucky (3) unw_init_local.3.gz

Provided by: libunwind-dev_1.6.2-3.1_amd64 bug

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);
       int unw_init_local2(unw_cursor_t *c, unw_context_t *ctxt, int flag);


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 is expected to be one provided by a call
       to unw_getcontext; as such, the  instruction  pointer  may  point  to  the  instruction  after  the  last
       instruction  of a function, and libunwind will back-up the instruction pointer before beginning a walk up
       the call stack. 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.  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.

       If  the unw_context_t is known to be a signal frame (i.e., from the third argument in a sigaction handler
       on linux), unw_init_local2() should be used for correct initialization on  some  platforms,  passing  the
       UNW_INIT_SIGNAL_FRAME flag.


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/.