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DWARF_GET_VARS(3)	 BSD 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 vari-
     ables 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	vari-
     ables 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 re-
     turned.

     Function dwarf_var_cu_offset() returns the	section-relative offset, rela-
     tive to the ".debug_info" section,	of the compilation unit	that contains
     the debugging information entry associated	with the argument var.	Argu-
     ment 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 associ-
     ated offsets for the debugging information	entry for argument var.	 Argu-
     ment 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 in-
     formation 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 de-
     bugging information entry in the compilation unit associated with argu-
     ment 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 di-
     rectly 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)

BSD				 April 2, 2011				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO

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