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unw_init_remote(3) [debian man page]

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_cre-
       ate_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-spa-
       ces  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  argu-
       ment 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 han-
       dler.

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
       Email: dmosberger@gmail.com
       WWW: http://www.nongnu.org/libunwind/.

Programming Library						  16 August 2007						UNW_INIT_REMOTE(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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