1\documentclass{article}
2\usepackage[fancyhdr,pdf]{latex2man}
3
4\input{common.tex}
5
6\begin{document}
7
8\begin{Name}{3}{unw\_init\_local}{David Mosberger-Tang}{Programming Library}{unw\_init\_local}unw\_init\_local -- initialize cursor for local unwinding
9\end{Name}
10
11\section{Synopsis}
12
13\File{\#include $<$libunwind.h$>$}\\
14
15\Type{int} \Func{unw\_init\_local}(\Type{unw\_cursor\_t~*}\Var{c}, \Type{unw\_context\_t~*}\Var{ctxt});\\
16
17\section{Description}
18
19The \Func{unw\_init\_local}() routine initializes the unwind cursor
20pointed to by \Var{c} with the machine-state in the context structure
21pointed to by \Var{ctxt}.  As such, the machine-state pointed to by
22\Var{ctxt} identifies the initial stack frame at which unwinding
23starts.  The machine-state must remain valid for the duration for
24which the cursor \Var{c} is in use.
25
26The \Func{unw\_init\_local}() routine can be used only for unwinding in
27the address space of the current process (i.e., for local unwinding).
28For all other cases, \Func{unw\_init\_remote}() must be used instead.
29From a behavioral point of view, the call:
30
31\begin{verbatim}
32    ret = unw_init_local(&cursor, &ucontext);
33\end{verbatim}
34is equivalent to:
35
36\begin{verbatim}
37    ret = unw_init_remote(&cursor, unw_local_addr_space,
38                          &ucontext);
39\end{verbatim}
40However, unwind performance may be better when using
41\Func{unw\_init\_local}().  Also, \Func{unw\_init\_local}() is
42available even when \Const{UNW\_LOCAL\_ONLY} has been defined before
43including \File{$<$libunwind.h$>$}, whereas \Func{unw\_init\_remote}()
44is not.
45
46\section{Return Value}
47
48On successful completion, \Func{unw\_init\_local}() returns 0.
49Otherwise the negative value of one of the error-codes below is
50returned.
51
52\section{Thread and Signal Safety}
53
54\Func{unw\_init\_local}() is thread-safe as well as safe to use from a
55signal handler.
56
57\section{Errors}
58
59\begin{Description}
60\item[\Const{UNW\_EINVAL}] \Func{unw\_init\_local}() was called in a
61  version of \Prog{libunwind} which supports remote unwinding only
62  (this normally happens when calling \Func{unw\_init\_local}() for a
63  cross-platform version of \Prog{libunwind}).
64\item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
65\item[\Const{UNW\_EBADREG}] A register needed by \Func{unw\_init\_local}()
66  wasn't accessible.
67\end{Description}
68
69\section{See Also}
70
71\SeeAlso{libunwind(3)}, \SeeAlso{unw\_init\_remote(3)}
72
73\section{Author}
74
75\noindent
76David Mosberger-Tang\\
77Email: \Email{dmosberger@gmail.com}\\
78WWW: \URL{http://www.nongnu.org/libunwind/}.
79\LatexManEnd
80
81\end{document}
82