unw_init_local(3) [debian 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)

UNW_SET_CACHING_POLICY(3)				       Programming Library					 UNW_SET_CACHING_POLICY(3)

NAME

       unw_set_caching_policy -- set unwind caching policy

SYNOPSIS

       #include <libunwind.h>

       int unw_set_caching_policy(unw_addr_space_t as, unw_caching_policy_t policy);

DESCRIPTION

       The  unw_set_caching_policy()  routine  sets the caching policy of address space as to the policy specified by argument policy.	The policy
       argument can take one of three possible values:

       UNW_CACHE_NONE
	       Turns off caching completely. This also implicitly flushes the contents of all caches as if unw_flush_cache() had been called.

       UNW_CACHE_GLOBAL
	       Enables caching using a global cache that is shared by all threads. If global caching is unavailable or unsupported, libunwind  may
	      fall back on using a per-thread cache, as if UNW_CACHE_PER_THREAD had been specified.

       UNW_CACHE_PER_THREAD
	       Enables	caching  using	thread-local  caches. If a thread-local caching are unavailable or unsupported, libunwind may fall back on
	      using a global cache, as if UNW_CACHE_GLOBAL had been specified.

       If caching is enabled, an application must be prepared to make appropriate calls to unw_flush_cache() whenever the target changes in a  way
       that  could  affect  the validity of cached information.  For example, after unloading (removing) a shared library, unw_flush_cache() would
       have to be called (at least) for the address-range that was covered by the shared library.

       For  address  spaces  created  via  unw_create_addr_space(3),  caching  is  turned  off	by  default.   For   the   local   address   space
       unw_local_addr_space, caching is turned on by default.

RETURN VALUE

       On successful completion, unw_set_caching_policy() returns 0.  Otherwise the negative value of one of the error-codes below is returned.

THREAD AND SIGNAL SAFETY

       unw_set_caching_policy() is thread-safe but not safe to use from a signal handler.

ERRORS

       UNW_ENOMEM
	       The desired caching policy could not be established because the application is out of memory.

SEE ALSO

       libunwind(3), unw_create_addr_space(3), unw_flush_cache(3)

AUTHOR

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

Programming Library						  16 August 2007					 UNW_SET_CACHING_POLICY(3)