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DWARF_GET_VARS(3)          Library Functions Manual          DWARF_GET_VARS(3)

NAME
     dwarf_get_vars, dwarf_var_cu_offset, dwarf_var_die_offset,
     dwarf_var_name_offsets, dwarf_varname - retrieve information about static
     variables

LIBRARY
     DWARF Access Library (libdwarf, -ldwarf)

SYNOPSIS
     #include <libdwarf.h>

     int
     dwarf_get_vars(Dwarf_Debug dbg, Dwarf_Var **vars, Dwarf_Signed *nvars,
         Dwarf_Error *err);

     int
     dwarf_var_cu_offset(Dwarf_Var var, Dwarf_Off *cu_offset,
         Dwarf_Error *err);

     int
     dwarf_var_die_offset(Dwarf_Var var, Dwarf_Off *die_offset,
         Dwarf_Error *err);

     int
     dwarf_var_name_offsets(Dwarf_Var var, char **name, Dwarf_Off *die_offset,
         Dwarf_Off *cu_die_offset, Dwarf_Error *err);

     int
     dwarf_varname(Dwarf_Var var, char **name, Dwarf_Error *err);

DESCRIPTION
     These functions retrieve information about the file scope static
     variables associated with a DWARF debug context.  Information about these
     static variables is returned using opaque descriptors of type Dwarf_Var.
     Applications need to use the functions described below to retrieve the
     name and offset information contained in these descriptors.

     Function dwarf_get_vars() retrieves descriptors for all the static
     variables associated with the DWARF debug context specified by argument
     dbg.  The argument vars should point to a location that will be set to a
     pointer to an array of Dwarf_Var descriptors.  The argument nvars should
     point to a location that will be set to the number of descriptors
     returned.

     Function dwarf_var_cu_offset() returns the section-relative offset,
     relative to the ".debug_info" section, of the compilation unit that
     contains the debugging information entry associated with the argument
     var.  Argument cu_offset should point to a location that will hold the
     returned offset.

     Function dwarf_var_die_offset() retrieves the section-relative offset,
     relative to the ".debug_info" section, of the debugging information entry
     associated with the argument var, and stores it into the location pointed
     to by the argument die_offset.

     Function dwarf_var_name_offsets() retrieves both the name and the
     associated offsets for the debugging information entry for argument var.
     Argument name should point to a location which will be set to a pointer
     to a NUL-terminated string containing the name of the associated
     debugging information entry.  Argument die_offset should point to a
     location which will be set to a section-relative offset, relative to the
     ".debug_info" section, of the associated debugging information entry.
     Argument cu_die_offset should point to a location which will be set to a
     section-relative offset, relative to the ".debug_info" section, of the
     first debugging information entry in the compilation unit associated with
     argument var.

     Function dwarf_varname() sets the location pointed to by argument name to
     a pointer to a NUL-terminated string holding the name of the debugging
     information entry associated with the argument var.

   Memory Management
     The memory area used for the array of Dwarf_Var descriptors returned in
     argument vars by function dwarf_get_vars() is owned by the DWARF Access
     Library (libdwarf, -ldwarf).  Application code should not attempt to
     directly free this pointer.  Portable code should instead use the
     function dwarf_vars_dealloc(3) to indicate that the memory area may be
     freed.

     The memory area used for the string returned in the name argument to
     functions dwarf_var_name_offsets() and dwarf_varname() is owned by the
     DWARF Access Library (libdwarf, -ldwarf).  Portable code should indicate
     that the memory area can be freed using the dwarf_dealloc(3) function.

   Error Returns
     If argument err is not NULL, these functions will use it to store error
     information, in case of an error.

RETURN VALUES
     On success, these functions returns DW_DLV_OK.  In case of an error, they
     return DW_DLV_ERROR and set the argument err.

ERRORS
     These functions may fail with the following errors:

     [DW_DLE_ARGUMENT]       One of the arguments cu_die_offset, cu_offset,
                             dbg, die_offset, var, vars, name, or nvars was
                             NULL.

SEE ALSO
     dwarf(3), dwarf_dealloc(3),
     dwarf_get_cu_die_offset_given_cu_header_offset(3), dwarf_vars_dealloc(3)

NetBSD 10.99                     April 2, 2011                    NetBSD 10.99