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      1 \documentclass{article}
      2 \usepackage[fancyhdr,pdf]{latex2man}
      3 
      4 \input{common.tex}
      5 
      6 \begin{document}
      7 
      8 \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
      9 \end{Name}
     10 
     11 \section{Synopsis}
     12 
     13 \File{\#include $<$libunwind.h$>$}\\
     14 
     15 \Type{int} \Func{unw\_get\_proc\_info}(\Type{unw\_cursor\_t~*}\Var{cp}, \Type{unw\_proc\_info\_t~*}\Var{pip});\\
     16 
     17 \section{Description}
     18 
     19 The \Func{unw\_get\_proc\_info}() routine returns auxiliary
     20 information about the procedure that created the stack frame
     21 identified by argument \Var{cp}.  The \Var{pip} argument is a pointer
     22 to a structure of type \Type{unw\_proc\_info\_t} which is used to
     23 return the information.  The \Type{unw\_proc\_info\_t} has the
     24 following members:
     25 \begin{description}
     26 \item[\Type{unw\_word\_t} \Var{start\_ip}] The address of the first
     27   instruction of the procedure.  If this address cannot be determined
     28   (e.g., due to lack of unwind information), the \Var{start\_ip}
     29   member is cleared to 0.  \\
     30 \item[\Type{unw\_word\_t} \Var{end\_ip}] The address of the first
     31   instruction \emph{beyond} the end of the procedure.  If this address
     32   cannot be determined (e.g., due to lack of unwind information),
     33   the \Var{end\_ip} member is cleared to 0.  \\
     34 \item[\Type{unw\_word\_t} \Var{lsda}] The address of the
     35   language-specific data-area (LSDA).  This area normally contains
     36   language-specific information needed during exception handling.  If
     37   the procedure has no such area, this member is cleared to 0.  \\
     38 \item[\Type{unw\_word\_t} \Var{handler}] The address of the exception
     39   handler routine.  This is sometimes called the \emph{personality}
     40   routine.  If the procedure does not define
     41   a personality routine, the \Var{handler} member is cleared to 0.  \\
     42 \item[\Type{unw\_word\_t} \Var{gp}] The global-pointer of the
     43   procedure.  On platforms that do not use a global pointer, this
     44   member may contain an undefined value.  On all other platforms, it
     45   must be set either to the correct global-pointer value of the
     46   procedure or to 0 if the proper global-pointer cannot be
     47   obtained for some reason.  \\
     48 \item[\Type{unw\_word\_t} \Var{flags}] A set of flags.  There are
     49   currently no target-independent flags.  For the IA-64 target, the
     50   flag \Const{UNW\_PI\_FLAG\_IA64\_RBS\_SWITCH} is set if the
     51   procedure may switch the register-backing store.\\
     52 \item[\Type{int} \Var{format}] The format of the unwind-info for this
     53   procedure.  If the unwind-info consists of dynamic procedure info,
     54   \Var{format} is equal to \Const{UNW\_INFO\_FORMAT\_DYNAMIC}.  If the
     55   unwind-info consists of a (target-specific) unwind table, it is
     56   equal to to \Const{UNW\_INFO\_FORMAT\_TABLE}.  All other values are
     57   reserved for future use by \Prog{libunwind}.  This member exists
     58   for use by the \Func{find\_proc\_info}() call-back (see
     59   \Func{unw\_create\_addr\_space}(3)).  The
     60   \Func{unw\_get\_proc\_info}() routine
     61   may return an undefined value in this member. \\
     62 \item[\Type{int} \Var{unwind\_info\_size}] The size of the unwind-info
     63   in bytes.  This member exists for use by the
     64   \Func{find\_proc\_info}() call-back (see
     65   \Func{unw\_create\_addr\_space}(3)).  The
     66   \Func{unw\_get\_proc\_info}() routine
     67   may return an undefined value in this member.\\
     68 \item[\Type{void~*}\Var{unwind\_info}] The pointer to the unwind-info.
     69   If no unwind info is available, this member must be set to
     70   \Const{NULL}.  This member exists for use by the
     71   \Func{find\_proc\_info}() call-back (see
     72   \Func{unw\_create\_addr\_space}(3)).  The
     73   \Func{unw\_get\_proc\_info}() routine
     74   may return an undefined value in this member.\\
     75 \end{description}
     76 Note that for the purposes of \Prog{libunwind}, the code of a
     77 procedure is assumed to occupy a single, contiguous range of
     78 addresses.  For this reason, it is alwas possible to describe the
     79 extent of a procedure with the \Var{start\_ip} and \Var{end\_ip}
     80 members.  If a single function/routine is split into multiple,
     81 discontiguous pieces, \Prog{libunwind} will treat each piece as a
     82 separate procedure.
     83 
     84 \section{Return Value}
     85 
     86 On successful completion, \Func{unw\_get\_proc\_info}() returns 0.
     87 Otherwise the negative value of one of the error-codes below is
     88 returned.
     89 
     90 \section{Thread and Signal Safety}
     91 
     92 \Func{unw\_get\_proc\_info}() is thread-safe.  If cursor \Var{cp} is
     93 in the local address-space, this routine is also safe to use from a
     94 signal handler.
     95 
     96 \section{Errors}
     97 
     98 \begin{Description}
     99 \item[\Const{UNW\_EUNSPEC}] An unspecified error occurred.
    100 \item[\Const{UNW\_ENOINFO}] \Prog{Libunwind} was unable to locate
    101   unwind-info for the procedure.
    102 \item[\Const{UNW\_EBADVERSION}] The unwind-info for the procedure has
    103   version or format that is not understood by \Prog{libunwind}.
    104 \end{Description}
    105 In addition, \Func{unw\_get\_proc\_info}() may return any error
    106 returned by the \Func{access\_mem}() call-back (see
    107 \Func{unw\_create\_addr\_space}(3)).
    108 
    109 \section{See Also}
    110 
    111 \SeeAlso{libunwind(3)},
    112 \SeeAlso{unw\_create\_addr\_space(3)},
    113 \SeeAlso{unw\_get\_proc\_name(3)}
    114 
    115 \section{Author}
    116 
    117 \noindent
    118 David Mosberger-Tang\\
    119 Email: \Email{dmosberger (a] gmail.com}\\
    120 WWW: \URL{http://www.nongnu.org/libunwind/}.
    121 \LatexManEnd
    122 
    123 \end{document}
    124