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UNW_IS_SIGNAL_FRAME(3)       Programming Library        UNW_IS_SIGNAL_FRAME(3)

NAME
       unw_is_signal_frame -- check if current frame is a signal frame

SYNOPSIS
       #include <libunwind.h>

       int unw_is_signal_frame(unw_cursor_t *cp);

DESCRIPTION
       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.

RETURN VALUE
       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
       returned.

THREAD AND SIGNAL SAFETY
       unw_is_signal_frame() is thread-safe as well as safe to use from a
       signal handler.

ERRORS
       UNW_ENOINFO
               Libunwind is unable to determine whether or not the current
              frame is a signal frame.

SEE ALSO
       libunwind(3), unw_get_reg(3), unw_set_reg(3), unw_get_fpreg(3),
       unw_set_fpreg(3)

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

Programming Library             16 August 2007          UNW_IS_SIGNAL_FRAME(3)