DragonFly On-Line Manual Pages
UNW_IS_SIGNAL_FRAME(3) Programming Library UNW_IS_SIGNAL_FRAME(3)
unw_is_signal_frame -- check if current frame is a signal frame
int unw_is_signal_frame(unw_cursor_t *cp);
The unw_is_signal_frame() routine returns a positive value if the
current frame identified by cp is a signal frame, and a value of 0
otherwise. For the purpose of this discussion, a signal frame is a
frame that was created in response to a potentially asynchronous
interruption. For UNIX and UNIX-like platforms, such frames are
normally created by the kernel when delivering a signal. In a
kernel-environment, a signal frame might, for example, correspond to a
frame created in response to a device interrupt.
Signal frames are somewhat unusual because the asynchronous nature of
the events that create them require storing the contents of registers
that are normally treated as scratch (``caller-saved'') registers.
On successful completion, unw_is_signal_frame() returns a positive
value if the current frame is a signal frame, or 0 if it is not.
Otherwise, a negative value of one of the error-codes below is
THREAD AND SIGNAL SAFETY
unw_is_signal_frame() is thread-safe as well as safe to use from a
Libunwind is unable to determine whether or not the current
frame is a signal frame.
libunwind(3), unw_get_reg(3), unw_set_reg(3), unw_get_fpreg(3),
Programming Library 16 August 2007 UNW_IS_SIGNAL_FRAME(3)