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Patch to work around lexgrog bug

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(Logical change 1.73)
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esiee.fr!m.delahaye 2003-03-31 19:57:09 +00:00
parent f20b6f8a4a
commit 972aec70ba
15 changed files with 624 additions and 18 deletions
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3
doc/libunwind-ia64.tex
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\begin{document}
\begin{Name}{3}{libunwind-ia64}{David Mosberger-Tang}{Programming Library}{IA-64-specific support in libunwind}
libunwind-ia64 -- IA-64-specific support in libunwind
\begin{Name}{3}{libunwind-ia64}{David Mosberger-Tang}{Programming Library}{IA-64-specific support in libunwind}libunwind-ia64 -- IA-64-specific support in libunwind
\end{Name}

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doc/libunwind-ptrace.tex
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\begin{document}
\begin{Name}{3}{libunwind-ptrace}{David Mosberger-Tang}{Programming Library}{ptrace() support in libunwind}
libunwind-ptrace -- ptrace() support in libunwind
\begin{Name}{3}{libunwind-ptrace}{David Mosberger-Tang}{Programming Library}{ptrace() support in libunwind}libunwind-ptrace -- ptrace() support in libunwind
\end{Name}
\section{Synopsis}

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doc/libunwind-setjmp.tex
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\begin{document}
\begin{Name}{3}{libunwind-setjmp}{David Mosberger-Tang}{Programming Library}{libunwind-based non-local gotos}
libunwind-setjmp -- libunwind-based non-local gotos
\begin{Name}{3}{libunwind-setjmp}{David Mosberger-Tang}{Programming Library}{libunwind-based non-local gotos}libunwind-setjmp -- libunwind-based non-local gotos
\end{Name}
\section{Synopsis}

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doc/libunwind.tex
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\begin{document}
\begin{Name}{3}{libunwind}{David Mosberger-Tang}{Programming Library}{Introduction to libunwind}
libunwind -- a (mostly) platform-independent unwind API
\begin{Name}{3}{libunwind}{David Mosberger-Tang}{Programming Library}{Introduction to libunwind}libunwind -- a (mostly) platform-independent unwind API
\end{Name}
\section{Synopsis}

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doc/unw_create_addr_space.tex
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\begin{document}
\begin{Name}{3}{unw\_create\_addr\_space}{David Mosberger-Tang}{Programming Library}{unw\_create\_addr\_space}
unw\_create\_addr\_space -- create address space for remote unwinding
\begin{Name}{3}{unw\_create\_addr\_space}{David Mosberger-Tang}{Programming Library}{unw\_create\_addr\_space}unw\_create\_addr\_space -- create address space for remote unwinding
\end{Name}
\section{Synopsis}

4
doc/unw_destroy_addr_space.tex
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\begin{document}
\begin{Name}{3}{unw\_destroy\_addr\_space}{David Mosberger-Tang}{Programming Library}{unw\_destroy\_addr\_space}
unw\_destroy\_addr\_space -- destroy unwind address space
\begin{Name}{3}{unw\_destroy\_addr\_space}{David Mosberger-Tang}{Programming Library}{unw\_destroy\_addr\_space}unw\_destroy\_addr\_space -- destroy unwind address space
\end{Name}
\section{Synopsis}

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doc/unw_flush_cache.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_flush\_cache}{David Mosberger-Tang}{Programming Library}{unw\_flush\_cache}unw\_flush\_cache -- flush cached info
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{void} \Func{unw\_flush\_cache}(\Type{unw\_addr\_space\_t} \Var{as}, \Type{unw\_word\_t} \Var{lo}, \Type{unw\_word\_t} \Var{hi});\\
\section{Description}
The \Func{unw\_flush\_cache}() routine flushes all cached info as it
relates to address-range \Var{lo} to \Var{hi} (non-inclusive) in the
target address-space \Var{as}. In addition, all info cached for
address-space \Var{as} that is not tied to a particular code-range is
also flushed. For example, the address of the dynamic registration
list is not tied to a code-range and its cached value (if any) is
flushed by a call to this routine. The address range specified by
\Var{lo} and \Var{hi} should be understood as a hint:
\Func{unw\_flush\_cache}() may flush more information than requested,
but \emph{never} less. In other words, \Func{unw\_flush\_cache}() may
overflush, but not underflush.
As a special case, if arguments \Var{lo} and \Var{hi} are both 0, all
information cached on behalf of address space \Var{as} is flushed.
\section{Return Value}
The \Func{unw\_flush\_cache}() routine cannot fail and does not
return a value.
\section{Thread and Signal Safety}
The \Func{unw\_flush\_cache}() routine is thread-safe as well as safe to
use from a signal handler.
\section{See Also}
\SeeAlso{libunwind(3)},
\SeeAlso{unw\_set\_caching\_policy(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}

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doc/unw_get_accessors.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_get\_accessors}{David Mosberger-Tang}{Programming Library}{unw\_get\_accessors}unw\_get\_accessors -- get pointer to accessor call-backs
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{unw\_accessors\_t~*}\Func{unw\_get\_accessors}(\Type{unw\_addr\_space\_t~}\Var{as});\\
\section{Description}
The \Func{unw\_get\_accessors}() routine returns a pointer to a
\Type{unw\_accessors\_t} structure, which contains the call-back
routines that were specified when address space \Var{as} was created
(see \Func{unw\_create\_addr\_space}(3)). The returned pointer is
guaranteed to remain valid until address space \Var{as} is destroyed
by a call to \Func{unw\_destroy\_addr\_space}(3).
Note that \Func{unw\_get\_accessors}() can be used to retrieve the
call-back routines for the local address space
\Var{unw\_local\_addr\_space}.
\section{Return Value}
The \Func{unw\_get\_accessors}() routine cannot fail and always
returns a valid (non-\Const{NULL}) pointer to an
\Type{unw\_accessors\_t} structure.
\section{Thread and Signal Safety}
The \Func{unw\_get\_accessors}() routine is thread-safe as well as
safe to use from a signal handler.
\section{See Also}
\SeeAlso{libunwind(3)},
\SeeAlso{unw\_create\_addr\_space(3)},
\SeeAlso{unw\_destroy\_addr\_space(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}

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doc/unw_get_proc_info.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_get\_proc\_info}{David Mosberger-Tang}{Programming Library}{unw\_get\_proc\_info}unw\_get\_proc\_info -- get info on current procedure
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{int} \Func{unw\_get\_proc\_info}(\Type{unw\_cursor\_t~*}\Var{cp}, \Type{unw\_proc\_info\_t~*}\Var{pip});\\
\section{Description}
The \Func{unw\_get\_proc\_info}() routine returns auxiliary
information about the procedure that created the stack frame
identified by argument \Var{cp}. The \Var{pip} argument is a pointer
to a structure of type \Type{unw\_proc\_info\_t} which is used to
return the information. The \Type{unw\_proc\_info\_t} has the
following members:
\begin{description}
\item[\Type{unw\_word\_t} \Var{start\_ip}] The address of the first
instruction of the procedure. If this address cannot be determined
(e.g., due to lack of unwind information), the \Var{start\_ip}
member is cleared to 0. \\
\item[\Type{unw\_word\_t} \Var{end\_ip}] The address of the first
instruction \emph{beyond} the end of the procedure. If this address
cannot be determined (e.g., due to lack of unwind information),
the \Var{end\_ip} member is cleared to 0. \\
\item[\Type{unw\_word\_t} \Var{lsda}] The address of the
language-specific data-area (LSDA). This area normally contains
language-specific information needed during exception handling. If
the procedure has no such area, this member is cleared to 0. \\
\item[\Type{unw\_word\_t} \Var{handler}] The address of the exception
handler routine. This is sometimes called the \emph{personality}
routine. If the procedure does not define
a personality routine, the \Var{handler} member is cleared to 0. \\
\item[\Type{unw\_word\_t} \Var{gp}] The global-pointer of the
procedure. On platforms that do not use a global pointer, this
member may contain an undefined value. On all other platforms, it
must be set either to the correct global-pointer value of the
procedure or to 0 if the proper global-pointer cannot be
obtained for some reason. \\
\item[\Type{unw\_word\_t} \Var{flags}] A set of flags. There are
currently no target-independent flags. For the IA-64 target, the
flag \Const{UNW_PI_FLAG_IA64_RBS_SWITCH} is set if the
procedure may switch the register-backing store.\\
\item[\Type{int} \Var{format}] The format of the unwind-info for this
procedure. If the unwind-info consists of dynamic procedure info,
\Var{format} is equal to \Const{UNW\_INFO\_FORMAT\_DYNAMIC}. If the
unwind-info consists of a (target-specific) unwind table, it is
equal to to \Const{UNW\_INFO\_FORMAT\_TABLE}. All other values are
reserved for future use by \Prog{libunwind}. This member exists
for use by the \Func{find\_proc\_info}() call-back (see
\Func{unw\_create\_addr\_space}(3)). The
\Func{unw\_get\_proc\_info}() routine
may return an undefined value in this member. \\
\item[\Type{int} \Var{unwind\_info\_size}] The size of the unwind-info
in bytes. This member exists for use by the
\Func{find\_proc\_info}() call-back (see
\Func{unw\_create\_addr\_space}(3)). The
\Func{unw\_get\_proc\_info}() routine
may return an undefined value in this member.\\
\item[\Type{void~*}\Var{unwind\_info}] The pointer to the unwind-info.
If no unwind info is available, this member must be set to
\Const{NULL}. This member exists for use by the
\Func{find\_proc\_info}() call-back (see
\Func{unw\_create\_addr\_space}(3)). The
\Func{unw\_get\_proc\_info}() routine
may return an undefined value in this member.\\
\end{description}
Note that for the purposes of \Prog{libunwind}, the code of a
procedure is assumed to occupy a single, contiguous range of
addresses. For this reason, it is alwas possible to describe the
extent of a procedure with the \Var{start\_ip} and \Var{end\_ip}
members. If a single function/routine is split into multiple,
discontiguous pieces, \Prog{libunwind} will treat each piece as a
separate procedure.
\section{Return Value}
On successful completion, \Func{unw\_get\_proc\_info}() returns 0.
Otherwise the negative value of one of the error-codes below is
returned.
\section{Thread and Signal Safety}
\Func{unw\_get\_proc\_info}() 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\_ENOINFO}] \Prog{Libunwind} was unable to locate
unwind-info for the procedure.
\item[\Const{UNW\_EBADVERSION}] The unwind-info for the procedure has
version or format that is not understood by \Prog{libunwind}.
\end{Description}
In addition, \Func{unw\_get\_proc\_info}() may return any error
returned by the \Func{access\_mem}() call-back (see
\Func{unw\_create\_addr\_space}(3)).
\section{See Also}
\SeeAlso{libunwind(3)},
\SeeAlso{unw\_create\_addr\_space(3)},
\SeeAlso{unw\_get\_proc\_name(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}

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doc/unw_get_proc_name.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_get\_proc\_name}{David Mosberger-Tang}{Programming Library}{unw\_get\_proc\_name}unw\_get\_proc\_name -- get name of current procedure
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{int} \Func{unw\_get\_proc\_name}(\Type{unw\_cursor\_t~*}\Var{cp}, \Type{char~*}\Var{bufp}, \Type{size\_t} \Var{len}, \Type{unw\_word\_t~*}\Var{offp});\\
\section{Description}
The \Func{unw\_get\_proc\_name}() routine returns the name of the
procedure that created the stack frame identified by argument
\Var{cp}. The \Var{bufp} argument is a pointer to a character buffer
that is at least \Var{len} bytes long. This buffer is used to return
the name of the procedure. The \Var{offp} argument is a pointer to a
word that is used to return the byte-offset of the instruction-pointer
saved in the stack frame identified by \Var{cp}, relative to the start
of the procedure. For example, if procedure \Func{foo}() starts at
address 0x40003000, then invoking \Func{unw\_get\_proc\_name}() on a
stack frame with an instruction-pointer value of 0x40003080 would
return a value of 0x80 in the word pointed to by \Var{offp} (assuming
the procedure is at least 0x80 bytes long).
Note that on some platforms there is no reliable way to distinguish
between procedure names and ordinary labels. Furthermore, if symbol
information has been stripped from a program, procedure names may be
completely unavailable or may be limited to those exported via a
dynamic symbol table. In such cases, \Func{unw\_get\_proc\_name}()
may return the name of a label or a preceeding (nearby) procedure.
However, the offset returned through \Var{offp} is always relative to
the returned name, which ensures that the value (address) of the
returned name plus the returned offset will always be equal to the
instruction-pointer of the stack frame identified by \Var{cp}.
\section{Return Value}
On successful completion, \Func{unw\_get\_proc\_name}() returns 0.
Otherwise the negative value of one of the error-codes below is
returned.
\section{Thread and Signal Safety}
\Func{unw\_get\_proc\_name}() is thread-safe but \emph{not} safe to
use from a signal handler.
\section{Errors}
\begin{Description}
\item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
\item[\Const{UNW\_ENOINFO}] \Prog{Libunwind} was unable to determine
the name of the procedure.
\item[\Const{UNW\_ENOMME}] The procedure name is too long to fit
in the buffer provided. A truncated version of the name has been
returned.
\end{Description}
In addition, \Func{unw\_get\_proc\_name}() may return any error
returned by the \Func{access\_mem}() call-back (see
\Func{unw\_create\_addr\_space}(3)).
\section{See Also}
\SeeAlso{libunwind(3)},
\SeeAlso{unw\_get\_proc\_info(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}

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doc/unw_init_local.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_init\_local}{David Mosberger-Tang}{Programming Library}{unw\_init\_local}unw\_init\_local -- initialize cursor for local unwinding
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{int} \Func{unw\_init\_local}(\Type{unw\_cursor\_t~*}\Var{c}, \Type{unw\_context\_t~*}\Var{ctxt});\\
\section{Description}
The \Func{unw\_init\_local}() routine initializes the unwind cursor
pointed to by \Var{c} with the machine-state in the context structure
pointed to by \Var{ctxt}. As such, the machine-state pointed to by
\Var{ctxt} identifies the initial stack frame at which unwinding
starts. The machine-state must remain valid for the duration for
which the cursor \Var{c} is in use.
The \Func{unw\_init\_local}() routine can be used only for unwinding in
the address space of the current process (i.e., for local unwinding).
For all other cases, \Func{unw\_init\_remote}() must be used instead.
From a behavioral point of view, the call:
\begin{verbatim}
ret = unw_init_local(&cursor, &ucontext);
\end{verbatim}
is equivalent to:
\begin{verbatim}
ret = unw_init_remote(&cursor, unw_local_addr_space,
&ucontext);
\end{verbatim}
However, unwind performance may be better when using
\Func{unw\_init\_local}(). Also, \Func{unw\_init\_local}() is
available even when \Const{UNW\_LOCAL\_ONLY} has been defined before
including \File{$<$libunwind.h$>$}, whereas \Func{unw\_init\_remote}()
is not.
\section{Return Value}
On successful completion, \Func{unw\_init\_local}() returns 0.
Otherwise the negative value of one of the error-codes below is
returned.
\section{Thread and Signal Safety}
\Func{unw\_init\_local}() is thread-safe as well as safe to use from a
signal handler.
\section{Errors}
\begin{Description}
\item[\Const{UNW\_EINVAL}] \Func{unw\_init\_local}() was called in a
version of \Prog{libunwind} which supports remote unwinding only
(this normally happens when calling \Func{unw\_init\_local}() for a
cross-platform version of \Prog{libunwind}).
\item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
\item[\Const{UNW\_EBADREG}] A register needed by \Func{unw\_init\_local}()
wasn't accessible.
\end{Description}
\section{See Also}
\SeeAlso{libunwind(3)}, \SeeAlso{unw\_init\_remote(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}

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doc/unw_init_remote.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_init\_remote}{David Mosberger-Tang}{Programming Library}{unw\_init\_remote}unw\_init\_remote -- initialize cursor for remote unwinding
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{int} \Func{unw\_init\_remote}(\Type{unw\_cursor\_t~*}\Var{c}, \Type{unw\_addr\_space\_t~}\Var{as}, \Type{void~*}\Var{arg});\\
\section{Description}
The \Func{unw\_init\_remote}() routine initializes the unwind cursor
pointed to by \Var{c} for unwinding in the address space identified by
\Var{as}. The \Var{as} argument can either be set to
\Var{unw\_local\_addr\_space} (local address space) or to an arbitrary
address space created with \Func{unw\_create\_addr\_space}().
The \Var{arg} void-pointer tells the address space exactly what entity
should be unwound. For example, if \Var{unw\_local\_addr\_space} is
passed in \Var{as}, then \Var{arg} needs to be a pointer to a context
structure containing the machine-state of the initial stack frame.
However, other address-spaces 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 \Var{arg} is entirely dependent on the address-space in use;
\Prog{libunwind} never interprets the argument in any way on its own.
Note that \Func{unw\_init\_remote}() can be used to initiate unwinding
in \emph{any} process, including the local process in which the
unwinder itself is running. However, for local unwinding, it is
generally preferable to use \Func{unw\_init\_local}() instead, because
it is easier to use and because it may perform better.
\section{Return Value}
On successful completion, \Func{unw\_init\_remote}() returns 0.
Otherwise the negative value of one of the error-codes below is
returned.
\section{Thread and Signal Safety}
\Func{unw\_init\_remote}() is thread-safe as well as safe to use from a
signal handler.
\section{Errors}
\begin{Description}
\item[\Const{UNW\_EINVAL}] \Func{unw\_init\_remote}() was called in a
version of \Prog{libunwind} which supports local unwinding only
(this normally happens when defining \Const{UNW\_LOCAL\_ONLY} before
including \File{$<$libunwind.h$>$} and then calling
\Func{unw\_init\_remote}()).
\item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
\item[\Const{UNW\_EBADREG}] A register needed by \Func{unw\_init\_remote}()
wasn't accessible.
\end{Description}
\section{See Also}
\SeeAlso{libunwind(3)}, \SeeAlso{unw\_create\_addr\_space(3)},
\SeeAlso{unw\_init\_local(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}

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doc/unw_regname.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_regname}{David Mosberger-Tang}{Programming Library}{unw\_regname}unw\_regname -- get register name
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{const char~*}\Func{unw\_regname}(\Type{unw\_regnum\_t} \Var{regnum});\\
\section{Description}
The \Func{unw\_regname}() routine returns a printable name for
register \Var{regnum}. If \Var{regnum} is an invalid or otherwise
unrecognized register number, a string consisting of three question
marks is returned. The returned string is statically allocated and
therefore guaranteed to remain valid until the application terminates.
\section{Return Value}
The \Func{unw\_regname}() routine cannot fail and always returns a
valid (non-\Const{NULL}) string.
\section{Thread and Signal Safety}
The \Func{unw\_regname}() routine is thread-safe as well as safe to
use from a signal handler.
\section{See Also}
\SeeAlso{libunwind(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}

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doc/unw_resume.tex
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\begin{document}
\begin{Name}{3}{unw\_resume}{David Mosberger-Tang}{Programming Library}{unw\_resume}
unw\_resume -- resume execution in a particular stack frame
\begin{Name}{3}{unw\_resume}{David Mosberger-Tang}{Programming Library}{unw\_resume}unw\_resume -- resume execution in a particular stack frame
\end{Name}
\section{Synopsis}

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doc/unw_set_caching_policy.tex
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\documentclass{article}
\usepackage[fancyhdr,pdf]{latex2man}
\input{common.tex}
\begin{document}
\begin{Name}{3}{unw\_set\_caching\_policy}{David Mosberger-Tang}{Programming Library}{unw\_set\_caching\_policy}unw\_set\_caching\_policy -- set unwind caching policy
\end{Name}
\section{Synopsis}
\File{\#include $<$libunwind.h$>$}\\
\Type{int} \Func{unw\_set\_caching\_policy}(\Type{unw\_addr\_space\_t} \Var{as}, \Type{unw\_caching_policy\_t} \Var{policy});\\
\section{Description}
The \Func{unw\_set\_caching\_policy}() routine sets the caching policy
of address space \Var{as} to the policy specified by argument
\Var{policy}. The \Var{policy} argument can take one of three
possible values:
\begin{description}
\item[\Const{UNW\_CACHE\_NONE}] Turns off caching completely. This
also implicitly flushes the contents of all caches as if
\Func{unw\_flush\_cache}() had been called.
\item[\Const{UNW\_CACHE\_GLOBAL}] Enables caching using a global cache
that is shared by all threads. If global caching is unavailable or
unsupported, \Prog{libunwind} may fall back on using a per-thread
cache, as if \Const{UNW\_CACHE\_PER\_THREAD} had been specified.
\item[\Const{UNW\_CACHE\_PER\_THREAD}] Enables caching using
thread-local caches. If a thread-local caching are unavailable or
unsupported, \Prog{libunwind} may fall back on using a global cache,
as if \Const{UNW\_CACHE\_GLOBAL} had been specified.
\end{description}
If caching is enabled, an application must be prepared to make
appropriate calls to \Func{unw\_flush\_cache}() whenever the target
changes in a way that could affect the validity of cached information.
For example, after unloading (removing) a shared library,
\Func{unw\_flush\_cache}() would have to be called (at least) for the
address-range that was covered by the shared library.
For address spaces created via \Func{unw\_create\_addr\_space}(3),
caching is turned off by default. For the local address space
\Func{unw\_local\_addr\_space}, caching is turned on by default.
\section{Return Value}
On successful completion, \Func{unw\_set\_caching\_policy}() returns 0.
Otherwise the negative value of one of the error-codes below is
returned.
\section{Thread and Signal Safety}
\Func{unw\_set\_caching\_policy}() is thread-safe but \emph{not} safe
to use from a signal handler.
\section{Errors}
\begin{Description}
\item[\Const{UNW\_ENOMEM}] The desired caching policy could not be
established because the application is out of memory.
\end{Description}
\section{See Also}
\SeeAlso{libunwind(3)},
\SeeAlso{unw\_create\_addr\_space(3)},
\SeeAlso{unw\_flush\_cache(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}