UNW_INIT_LOCAL(3libunwind)   Programming Library    UNW_INIT_LOCAL(3libunwind)

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(3libunwind), unw_init_remote(3libunwind)

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

Programming Library             29 August 2023      UNW_INIT_LOCAL(3libunwind)