Provided by: libunwind-dev_1.8.1-0.1ubuntu1_amd64 bug

NAME
       unw_get_reg -- get register contents


SYNOPSIS
       #include <libunwind.h>

       int unw_get_reg(unw_cursor_t *cp, unw_regnum_t reg, unw_word_t *valp);


DESCRIPTION
       The  unw_get_reg() routine reads the value of register reg in the stack frame identified by cursor cp and
       stores the value in the word pointed to by valp.

       The  register  numbering  is  target  dependent  and  described   in   separate   manual   pages   (e.g.,
       libunwind-ia64(3libunwind) 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(3libunwind)), it is usually possible
       to access all registers.

       Note that unw_get_reg() can only read the contents of registers whose values fit in a  single  word.  See
       unw_get_fpreg(3libunwind) for a way to read registers which do not fit this constraint.


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


THREAD AND SIGNAL SAFETY
       unw_get_reg() 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_reg()  may  return  any  error  returned  by  the  access_mem(), access_reg(), and
       access_fpreg() callbacks (see unw_create_addr_space(3libunwind)).


SEE ALSO
       libunwind(3libunwind),               libunwind-ia64(3libunwind),               unw_get_fpreg(3libunwind),
       unw_is_signal_frame(3libunwind), unw_set_reg(3libunwind)


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

Programming Library                              29 August 2023                          UNW_GET_REG(3libunwind)