unw_get_fpreg(3) [debian man page]

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).  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_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_cre-
       ate_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)

UNW_INIT_REMOTE(3)					       Programming Library						UNW_INIT_REMOTE(3)

NAME

       unw_init_remote -- initialize cursor for remote unwinding

SYNOPSIS

       #include <libunwind.h>

       int unw_init_remote(unw_cursor_t *c, unw_addr_space_t as, void *arg);

DESCRIPTION

       The  unw_init_remote()  routine	initializes the unwind cursor pointed to by c for unwinding in the address space identified by as.  The as
       argument can either be set to unw_local_addr_space  (local  address  space)  or	to  an	arbitrary  address  space  created  with  unw_cre-
       ate_addr_space().

       The  arg  void-pointer tells the address space exactly what entity should be unwound. For example, if unw_local_addr_space is passed in as,
       then arg needs to be a pointer to a context structure containing the machine-state of the initial stack frame.  However, other address-spa-
       ces  may  instead  expect  a  process-id,  a thread-id, or a pointer to an arbitrary structure which identifies the stack-frame chain to be
       unwound. In other words, the interpretation of arg is entirely dependent on the address-space in use; libunwind never interprets the  argu-
       ment in any way on its own.

       Note  that  unw_init_remote() can be used to initiate unwinding in any process, including the local process in which the unwinder itself is
       running. However, for local unwinding, it is generally preferable to use unw_init_local() instead, because it is easier to use and  because
       it may perform better.

RETURN VALUE

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

THREAD AND SIGNAL SAFETY

       unw_init_remote()  is thread-safe. If the local address-space is passed in argument as, this routine is also safe to use from a signal han-
       dler.

ERRORS

       UNW_EINVAL
	       unw_init_remote() was called in a version of libunwind which supports local unwinding only (this  normally  happens  when  defining
	      UNW_LOCAL_ONLY before including <libunwind.h> and then calling unw_init_remote()).

       UNW_EUNSPEC
	       An unspecified error occurred.

       UNW_EBADREG
	       A register needed by unw_init_remote() wasn't accessible.

SEE ALSO

       libunwind(3), unw_create_addr_space(3), unw_init_local(3)

AUTHOR

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

Programming Library						  16 August 2007						UNW_INIT_REMOTE(3)