DragonFly On-Line Manual Pages

Search: Section:  

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_set_cache_size(3),
       unw_flush_cache(3)


AUTHOR

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

Programming Library            02 December 2016      UNW_SET_CACHING_POLICY(3)

Search: Section: