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UNW_INIT_REMOTE(3) Programming Library UNW_INIT_REMOTE(3)
NAME
unw_init_remote -- initialize cursor for remote unwinding
SYNOPSIS
#include <libunwind.h>
int unw_init_remote(unw_cursor_t *c, unw_addr_space_t as, void *arg);
DESCRIPTION
The unw_init_remote() routine initializes the unwind cursor pointed to
by c for unwinding in the address space identified by as. The as
argument can either be set to unw_local_addr_space (local address
space) or to an arbitrary address space created with
unw_create_addr_space().
The arg void-pointer tells the address space exactly what entity should
be unwound. For example, if unw_local_addr_space is passed in as, then
arg needs to be a pointer to a context structure containing the
machine-state of the initial stack frame. However, other
address-spaces may instead expect a process-id, a thread-id, or a
pointer to an arbitrary structure which identifies the stack-frame
chain to be unwound. In other words, the interpretation of arg is
entirely dependent on the address-space in use; libunwind never
interprets the argument in any way on its own.
Note that unw_init_remote() can be used to initiate unwinding in any
process, including the local process in which the unwinder itself is
running. However, for local unwinding, it is generally preferable to
use unw_init_local() instead, because it is easier to use and because
it may perform better.
RETURN VALUE
On successful completion, unw_init_remote() returns 0. Otherwise the
negative value of one of the error-codes below is returned.
THREAD AND SIGNAL SAFETY
unw_init_remote() 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_EINVAL
unw_init_remote() was called in a version of libunwind which
supports local unwinding only (this normally happens when
defining UNW_LOCAL_ONLY before including <libunwind.h> and then
calling unw_init_remote()).
UNW_EUNSPEC
An unspecified error occurred.
UNW_EBADREG
A register needed by unw_init_remote() wasn't accessible.
SEE ALSO
libunwind(3), unw_create_addr_space(3), unw_init_local(3)
AUTHOR
David Mosberger-Tang