Version: 3.1.1

#include <wx/dynlib.h>

Detailed Description

wxDynamicLibrary is a class representing dynamically loadable library (Windows DLL, shared library under Unix etc).

Just create an object of this class to load a library and don't worry about unloading it – it will be done in the objects destructor automatically.

The following flags can be used with wxDynamicLibrary() or Load():

Styles

This class supports the following styles:

  • wxDL_LAZY:
    Equivalent of RTLD_LAZY under Unix, ignored elsewhere.
  • wxDL_NOW:
    Equivalent of RTLD_NOW under Unix, ignored elsewhere.
  • wxDL_GLOBAL:
    Equivalent of RTLD_GLOBAL under Unix, ignored elsewhere.
  • wxDL_VERBATIM:
    Don't try to append the appropriate extension to the library name (this is done by default).
  • wxDL_DEFAULT:
    Default flags, same as wxDL_NOW currently.
  • wxDL_QUIET:
    Don't log an error message if the library couldn't be loaded.

Library:  wxBase
Category:  Application and Process Management

Public Member Functions

 wxDynamicLibrary ()
 Default constructor. More...
 
 wxDynamicLibrary (const wxString &name, int flags=wxDL_DEFAULT)
 Constructor. More...
 
wxDllType Detach ()
 Detaches this object from its library handle, i.e. the object will not unload the library any longer in its destructor but it is now the callers responsibility to do this using Unload(). More...
 
void * GetSymbol (const wxString &name, bool *success=0) const
 Returns pointer to symbol name in the library or NULL if the library contains no such symbol. More...
 
void * GetSymbolAorW (const wxString &name) const
 This function is available only under Windows as it is only useful when dynamically loading symbols from standard Windows DLLs. More...
 
bool HasSymbol (const wxString &name) const
 Returns true if the symbol with the given name is present in the dynamic library, false otherwise. More...
 
bool IsLoaded () const
 Returns true if the library was successfully loaded, false otherwise. More...
 
bool Load (const wxString &name, int flags=wxDL_DEFAULT)
 Loads DLL with the given name into memory. More...
 
void Unload ()
 Unloads the library from memory. More...
 

Static Public Member Functions

static wxString GetDllExt (wxDynamicLibraryCategory cat=wxDL_LIBRARY)
 Returns the platform-specific dynamic library file extension, or depending on flags, the plugin file extension. More...
 
static wxString CanonicalizeName (const wxString &name, wxDynamicLibraryCategory cat=wxDL_LIBRARY)
 Returns the platform-specific full name for the library called name. More...
 
static wxString CanonicalizePluginName (const wxString &name, wxPluginCategory cat=wxDL_PLUGIN_GUI)
 This function does the same thing as CanonicalizeName() but for wxWidgets plugins. More...
 
static wxDllType GetProgramHandle ()
 Return a valid handle for the main program itself or NULL if symbols from the main program can't be loaded on this platform. More...
 
static wxDynamicLibraryDetailsArray ListLoaded ()
 This static method returns a wxArray containing the details of all modules loaded into the address space of the current project. More...
 
static void * GetModuleFromAddress (const void *addr, wxString *path=NULL)
 Returns the load address of the module containing the specified address or NULL if not found. More...
 
static void Unload (wxDllType handle)
 Unloads the library from memory. More...
 

Constructor & Destructor Documentation

wxDynamicLibrary::wxDynamicLibrary ( )

Default constructor.

wxDynamicLibrary::wxDynamicLibrary ( const wxString name,
int  flags = wxDL_DEFAULT 
)

Constructor.

Calls Load() with the given name.

Member Function Documentation

static wxString wxDynamicLibrary::CanonicalizeName ( const wxString name,
wxDynamicLibraryCategory  cat = wxDL_LIBRARY 
)
static

Returns the platform-specific full name for the library called name.

E.g. it adds a ".dll" extension under Windows and "lib" prefix and ".so", ".sl" or ".dylib" extension under Unix.

See also
CanonicalizePluginName()
static wxString wxDynamicLibrary::CanonicalizePluginName ( const wxString name,
wxPluginCategory  cat = wxDL_PLUGIN_GUI 
)
static

This function does the same thing as CanonicalizeName() but for wxWidgets plugins.

The only difference is that compiler and version information are added to the name to ensure that the plugin which is going to be loaded will be compatible with the main program.

wxDllType wxDynamicLibrary::Detach ( )

Detaches this object from its library handle, i.e. the object will not unload the library any longer in its destructor but it is now the callers responsibility to do this using Unload().

static wxString wxDynamicLibrary::GetDllExt ( wxDynamicLibraryCategory  cat = wxDL_LIBRARY)
static

Returns the platform-specific dynamic library file extension, or depending on flags, the plugin file extension.

The leading dot is included.

For example, on Windows ".dll" is returned, and either ".dylib" or ".bundle" on OS X.

static void* wxDynamicLibrary::GetModuleFromAddress ( const void *  addr,
wxString path = NULL 
)
static

Returns the load address of the module containing the specified address or NULL if not found.

If the second argument path is not NULL, it is filled with the full path to the file the module was loaded from upon a successful return.

This method is implemented under MSW and Unix platforms providing dladdr() call (which include Linux and various BSD systems) and always returns NULL elsewhere.

Since
3.1.0
static wxDllType wxDynamicLibrary::GetProgramHandle ( )
static

Return a valid handle for the main program itself or NULL if symbols from the main program can't be loaded on this platform.

void* wxDynamicLibrary::GetSymbol ( const wxString name,
bool *  success = 0 
) const

Returns pointer to symbol name in the library or NULL if the library contains no such symbol.

See also
wxDYNLIB_FUNCTION()
void* wxDynamicLibrary::GetSymbolAorW ( const wxString name) const

This function is available only under Windows as it is only useful when dynamically loading symbols from standard Windows DLLs.

Such functions have either 'A' (in ANSI build) or 'W' (in Unicode, or wide character build) suffix if they take string parameters. Using this function, you can use just the base name of the function and the correct suffix is appended automatically depending on the current build. Otherwise, this method is identical to GetSymbol().

Availability:  only available for the wxMSW port.
bool wxDynamicLibrary::HasSymbol ( const wxString name) const

Returns true if the symbol with the given name is present in the dynamic library, false otherwise.

Unlike GetSymbol(), this function doesn't log an error message if the symbol is not found.

Since
2.5.4
bool wxDynamicLibrary::IsLoaded ( ) const

Returns true if the library was successfully loaded, false otherwise.

static wxDynamicLibraryDetailsArray wxDynamicLibrary::ListLoaded ( )
static

This static method returns a wxArray containing the details of all modules loaded into the address space of the current project.

The array elements are objects of the type: wxDynamicLibraryDetails. The array will be empty if an error occurred.

This method is currently implemented only under Win32 and Linux and is useful mostly for diagnostics purposes.

bool wxDynamicLibrary::Load ( const wxString name,
int  flags = wxDL_DEFAULT 
)

Loads DLL with the given name into memory.

The flags argument can be a combination of the styles outlined in the class description.

Returns true if the library was successfully loaded, false otherwise.

void wxDynamicLibrary::Unload ( )

Unloads the library from memory.

wxDynamicLibrary object automatically calls this method from its destructor if it had been successfully loaded.

static void wxDynamicLibrary::Unload ( wxDllType  handle)
static

Unloads the library from memory.

wxDynamicLibrary object automatically calls this method from its destructor if it had been successfully loaded.

This version of Unload() is only used if you need to keep the library in memory during a longer period of time than the scope of the wxDynamicLibrary object. In this case you may call Detach() and store the handle somewhere and call this static method later to unload it.