2003-04-01 09:19:34 +02:00
|
|
|
\documentclass{article}
|
|
|
|
|
\usepackage[fancyhdr,pdf]{latex2man}
|
|
|
|
|
|
|
|
|
|
\input{common.tex}
|
|
|
|
|
|
|
|
|
|
\begin{document}
|
|
|
|
|
|
|
|
|
|
\begin{Name}{3}{unw\_get\_reg}{David Mosberger-Tang}{Programming Library}{unw\_get\_reg}unw\_get\_reg -- get register contents
|
|
|
|
|
\end{Name}
|
|
|
|
|
|
|
|
|
|
\section{Synopsis}
|
|
|
|
|
|
|
|
|
|
\File{\#include $<$libunwind.h$>$}\\
|
|
|
|
|
|
|
|
|
|
\Type{int} \Func{unw\_get\_reg}(\Type{unw\_cursor\_t~*}\Var{cp}, \Type{unw\_regnum\_t} \Var{reg}, \Type{unw\_word\_t~*}\Var{valp});\\
|
|
|
|
|
|
|
|
|
|
\section{Description}
|
|
|
|
|
|
|
|
|
|
The \Func{unw\_get\_reg}() routine reads the value of register
|
|
|
|
|
\Var{reg} in the stack frame identified by cursor \Var{cp} and stores
|
|
|
|
|
the value in the word pointed to by \Var{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 \Var{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
|
|
|
|
|
\Func{unw\_is\_signal\_frame}(3)), it is usually possible to access
|
|
|
|
|
all registers.
|
|
|
|
|
|
|
|
|
|
Note that \Func{unw\_get\_reg}() can only read the contents of
|
|
|
|
|
registers whose values fit in a single word. See
|
|
|
|
|
\Func{unw\_get\_fpreg}(3) for a way to read registers which do not fit
|
|
|
|
|
this constraint.
|
|
|
|
|
|
|
|
|
|
\section{Return Value}
|
|
|
|
|
|
|
|
|
|
On successful completion, \Func{unw\_get\_reg}() returns 0.
|
|
|
|
|
Otherwise the negative value of one of the error-codes below is
|
|
|
|
|
returned.
|
|
|
|
|
|
|
|
|
|
\section{Thread and Signal Safety}
|
|
|
|
|
|
|
|
|
|
\Func{unw\_get\_reg}() is thread-safe as well as safe to use
|
|
|
|
|
from a signal handler.
|
|
|
|
|
|
|
|
|
|
\section{Errors}
|
|
|
|
|
|
|
|
|
|
\begin{Description}
|
|
|
|
|
\item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
|
|
|
|
|
\item[\Const{UNW\_EBADREG}] An attempt was made to read a register
|
|
|
|
|
that is either invalid or not accessible in the current frame.
|
|
|
|
|
\end{Description}
|
|
|
|
|
In addition, \Func{unw\_get\_reg}() may return any error returned by
|
|
|
|
|
the \Func{access\_mem}(), \Func{access\_reg}(), and
|
|
|
|
|
\Func{access\_fpreg}() call-backs (see
|
|
|
|
|
\Func{unw\_create\_addr\_space}(3)).
|
|
|
|
|
|
|
|
|
|
\section{See Also}
|
|
|
|
|
|
|
|
|
|
\SeeAlso{libunwind(3)},
|
|
|
|
|
\SeeAlso{libunwind-ia64(3)},
|
|
|
|
|
\SeeAlso{unw\_get\_fpreg(3)},
|
|
|
|
|
\SeeAlso{unw\_is\_signal\_frame(3)},
|
|
|
|
|
\SeeAlso{unw\_set\_reg(3)}
|
|
|
|
|
|
|
|
|
|
\section{Author}
|
|
|
|
|
|
|
|
|
|
\noindent
|
|
|
|
|
David Mosberger-Tang\\
|
|
|
|
|
Hewlett-Packard Labs\\
|
|
|
|
|
Palo-Alto, CA 94304\\
|
|
|
|
|
Email: \Email{davidm@hpl.hp.com}\\
|
|
|
|
|
WWW: \URL{http://www.hpl.hp.com/research/linux/libunwind/}.
|
|
|
|
|
\LatexManEnd
|
|
|
|
|
|
|
|
|
|
\end{document}
|
