UNW_SET_FPREG(3)					       Programming Library						  UNW_SET_FPREG(3)

NAME

       unw_set_fpreg -- set contents of floating-point register

SYNOPSIS

       #include <libunwind.h>

       int unw_set_fpreg(unw_cursor_t *cp, unw_regnum_t reg, unw_fpreg_t val);

DESCRIPTION

       The unw_set_fpreg() routine sets the value of register reg in the stack frame identified by cursor cp to the value passed in val.

       The register numbering is target-dependent and described in separate manual pages (e.g., libunwind-ia64(3) for the IA-64 target).  Further-
       more, the exact set of accessible registers may depend on the type of frame that cp is referring to. For ordinary stack frames, it is  nor-
       mally  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_set_fpreg() can only write the contents of floating-point registers. See unw_set_reg(3) for a way to  write  registers  which
       fit in a single word.

RETURN VALUE

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

THREAD AND SIGNAL SAFETY

       unw_set_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 write a register that is either invalid or not accessible in the current frame.

       UNW_EREADONLY
	       An attempt was made to write to a read-only register.

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

SEE ALSO

       libunwind(3), libunwind-ia64(3), unw_get_fpreg(3), unw_is_fpreg(3), unw_is_signal_frame(3), unw_set_reg(3)

AUTHOR

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

Programming Library						  16 August 2007						  UNW_SET_FPREG(3)