Use (void) for function prototypes with no parameters

This is required when compiling these headers as C code. These were
omitted becuase before the addition of examples these headers were
only compiled locally as C++ files where adding the void keyword is
not needed.

include/SFML/Audio/Listener.h

@@ -68,7 +68,7 @@ CSFML_AUDIO_API void sfListener_setPosition(sfVector3f position);
 /// \return The listener's position
 ///
 ////////////////////////////////////////////////////////////
-CSFML_AUDIO_API sfVector3f sfListener_getPosition();
+CSFML_AUDIO_API sfVector3f sfListener_getPosition(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Set the orientation of the forward vector in the scene
@@ -91,7 +91,7 @@ CSFML_AUDIO_API void sfListener_setDirection(sfVector3f direction);
 /// \return Listener's forward vector (not normalized)
 ///
 ////////////////////////////////////////////////////////////
-CSFML_AUDIO_API sfVector3f sfListener_getDirection();
+CSFML_AUDIO_API sfVector3f sfListener_getDirection(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Set the upward vector of the listener in the scene
@@ -114,7 +114,7 @@ CSFML_AUDIO_API void sfListener_setUpVector(sfVector3f upVector);
 /// \return Listener's upward vector (not normalized)
 ///
 ////////////////////////////////////////////////////////////
-CSFML_AUDIO_API sfVector3f sfListener_getUpVector();
+CSFML_AUDIO_API sfVector3f sfListener_getUpVector(void);
 
 
 #endif // SFML_LISTENER_H

include/SFML/Audio/SoundRecorder.h

@@ -157,7 +157,7 @@ CSFML_AUDIO_API const char** sfSoundRecorder_getAvailableDevices(size_t* count);
 /// \return The name of the default audio capture device (null terminated)
 ///
 ////////////////////////////////////////////////////////////
-CSFML_AUDIO_API const char* sfSoundRecorder_getDefaultDevice();
+CSFML_AUDIO_API const char* sfSoundRecorder_getDefaultDevice(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Set the audio capture device

include/SFML/Config.h

@@ -119,7 +119,7 @@
 //     ...
 // };
 //
-// CSFML_DEPRECATED void globalFunc();
+// CSFML_DEPRECATED void globalFunc(void);
 ////////////////////////////////////////////////////////////
 #if defined(CSFML_NO_DEPRECATED_WARNINGS)
 

include/SFML/Graphics/RenderStates.h

@@ -50,6 +50,6 @@ typedef struct
 /// \brief Define the default values for a RenderState
 ///
 ////////////////////////////////////////////////////////////
-CSFML_GRAPHICS_API sfRenderStates sfRenderStates_default();
+CSFML_GRAPHICS_API sfRenderStates sfRenderStates_default(void);
 
 #endif // SFML_RENDERSTATES_H

include/SFML/Graphics/RenderTexture.h

@@ -326,7 +326,7 @@ CSFML_GRAPHICS_API const sfTexture* sfRenderTexture_getTexture(const sfRenderTex
 /// \return The maximum anti-aliasing level supported by the system
 ///
 ////////////////////////////////////////////////////////////
-CSFML_GRAPHICS_API unsigned int sfRenderTexture_getMaximumAntialiasingLevel();
+CSFML_GRAPHICS_API unsigned int sfRenderTexture_getMaximumAntialiasingLevel(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Enable or disable the smooth filter on a render texture

include/SFML/Graphics/Texture.h

@@ -403,7 +403,7 @@ CSFML_GRAPHICS_API void sfTexture_bind(const sfTexture* texture, sfTextureCoordi
 /// \return Maximum size allowed for textures, in pixels
 ///
 ////////////////////////////////////////////////////////////
-CSFML_GRAPHICS_API unsigned int sfTexture_getMaximumSize();
+CSFML_GRAPHICS_API unsigned int sfTexture_getMaximumSize(void);
 
 
 #endif // SFML_TEXTURE_H

include/SFML/Graphics/VertexBuffer.h

@@ -248,7 +248,7 @@ CSFML_GRAPHICS_API void sfVertexBuffer_bind(const sfVertexBuffer* vertexBuffer);
 /// \return True if vertex buffers are supported, false otherwise
 ///
 ////////////////////////////////////////////////////////////
-CSFML_GRAPHICS_API sfBool sfVertexBuffer_isAvailable();
+CSFML_GRAPHICS_API sfBool sfVertexBuffer_isAvailable(void);
 
 
 #endif // SFML_VERTEXBUFFER_H

include/SFML/Network/UdpSocket.h

@@ -203,7 +203,7 @@ CSFML_NETWORK_API sfSocketStatus sfUdpSocket_receivePacket(sfUdpSocket* socket,
 /// \return The maximum size of a UDP datagram (message)
 ///
 ////////////////////////////////////////////////////////////
-CSFML_NETWORK_API unsigned int sfUdpSocket_maxDatagramSize();
+CSFML_NETWORK_API unsigned int sfUdpSocket_maxDatagramSize(void);
 
 
 #endif // SFML_UDPSOCKET_H

include/SFML/Window/Clipboard.h

@@ -42,7 +42,7 @@
 /// \return Clipboard contents as a locale-dependent ANSI string
 ///
 ////////////////////////////////////////////////////////////
-CSFML_WINDOW_API const char* sfClipboard_getString();
+CSFML_WINDOW_API const char* sfClipboard_getString(void);
 
 
 ////////////////////////////////////////////////////////////
@@ -55,7 +55,7 @@ CSFML_WINDOW_API const char* sfClipboard_getString();
 /// \return Clipboard contents as UTF-32
 ///
 ////////////////////////////////////////////////////////////
-CSFML_WINDOW_API const sfUint32* sfClipboard_getUnicodeString();
+CSFML_WINDOW_API const sfUint32* sfClipboard_getUnicodeString(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Set the content of the clipboard as ANSI string data

include/SFML/Window/Context.h

@@ -32,7 +32,7 @@
 #include <SFML/Window/Types.h>
 #include <SFML/Window/Window.h>
 
-typedef void (*GlFunctionPointer)();
+typedef void (*GlFunctionPointer)(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Create a new context
@@ -104,6 +104,6 @@ CSFML_WINDOW_API sfContextSettings sfContext_getSettings(const sfContext* contex
 /// \return The active context's ID or 0 if no context is currently active
 ///
 ////////////////////////////////////////////////////////////
-CSFML_WINDOW_API sfUint64 sfContext_getActiveContextId();
+CSFML_WINDOW_API sfUint64 sfContext_getActiveContextId(void);
 
 #endif // SFML_CONTEXT_H

include/SFML/Window/Vulkan.h

@@ -43,7 +43,7 @@ typedef uint64_t VkSurfaceKHR;
 typedef struct VkAllocationCallbacks VkAllocationCallbacks;
 
 
-typedef void (*sfVulkanFunctionPointer)();
+typedef void (*sfVulkanFunctionPointer)(void);
 
 ////////////////////////////////////////////////////////////
 /// \brief Tell whether or not the system supports Vulkan
@@ -79,4 +79,4 @@ CSFML_WINDOW_API sfVulkanFunctionPointer sfVulkan_getFunction(const char* name);
 /// \return Vulkan instance extensions required for graphics
 ///
 ////////////////////////////////////////////////////////////
-CSFML_WINDOW_API const char* const* sfVulkan_getGraphicsRequiredInstanceExtensions();
+CSFML_WINDOW_API const char* const* sfVulkan_getGraphicsRequiredInstanceExtensions(void);