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UNW_GET_FPREG(3)             Programming Library              UNW_GET_FPREG(3)


NAME

       unw_get_fpreg -- get contents of floating-point register


SYNOPSIS

       #include <libunwind.h>

       int unw_get_fpreg(unw_cursor_t *cp, unw_regnum_t reg, unw_fpreg_t
       *valp);


DESCRIPTION

       The unw_get_fpreg() routine reads the value of floating-point register
       reg in the stack frame identified by cursor cp and stores the value in
       the variable pointed to by valp.

       The register numbering is target-dependent and described in separate
       manual pages (e.g., libunwind-ia64(3) for the IA-64 target).
       Furthermore, the exact set of accessible registers may depend on the
       type of frame that cp is referring to. For ordinary stack frames, it is
       normally possible to access only the preserved (``callee-saved'')
       registers and frame-related registers (such as the stack-pointer).
       However, for signal frames (see unw_is_signal_frame(3)), it is usually
       possible to access all registers.

       Note that unw_get_fpreg() can only read the contents of floating-point
       registers. See unw_get_fpreg(3) for a way to read registers which fit
       in a single word.


RETURN VALUE

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


THREAD AND SIGNAL SAFETY

       unw_get_fpreg() is thread-safe as well as safe to use from a signal
       handler.


ERRORS

       UNW_EUNSPEC
               An unspecified error occurred.

       UNW_EBADREG
               An attempt was made to read a register that is either invalid
              or not accessible in the current frame.

       In addition, unw_get_fpreg() may return any error returned by the
       access_mem(), access_reg(), and access_fpreg() call-backs (see
       unw_create_addr_space(3)).


SEE ALSO

       libunwind(3), libunwind-ia64(3), unw_get_reg(3), unw_is_fpreg(3),
       unw_is_signal_frame(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_GET_FPREG(3)

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