Add SDL_Process subsystem

Android.mk

@@ -57,6 +57,8 @@ LOCAL_SRC_FILES := \
 	$(wildcard $(LOCAL_PATH)/src/misc/android/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/power/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/power/android/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/process/*.c) \
+	$(wildcard $(LOCAL_PATH)/src/process/dummy/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/filesystem/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/filesystem/android/*.c) \
 	$(wildcard $(LOCAL_PATH)/src/filesystem/posix/*.c) \

CMakeLists.txt

@@ -2860,6 +2860,55 @@ if (SDL_DIALOG)
   endif()
 endif()
 
+sdl_sources("${SDL3_SOURCE_DIR}/src/process/SDL_process.c")
+if(WINDOWS)
+  sdl_glob_sources("${SDL3_SOURCE_DIR}/src/process/windows/*.c")
+  set(SDL_PROCESS_WINDOWS 1)
+  set(HAVE_SDL_PROCESS TRUE)
+else()
+  check_c_source_compiles("
+#include <spawn.h>
+#include <unistd.h>
+
+int main(void)
+{
+    int pipes[2];
+    int pid;
+
+    const char * args[] = {
+      \"/bin/false\",
+      NULL
+    };
+
+    const char * env[] = { NULL };
+
+    pipe(pipes);
+
+    posix_spawnattr_t attr;
+    posix_spawn_file_actions_t fa;
+
+    posix_spawnattr_init(&attr);
+    posix_spawn_file_actions_init(&fa);
+
+    posix_spawn_file_actions_addclose(&fa, pipes[0]);
+    posix_spawn_file_actions_adddup2(&fa, pipes[1], STDOUT_FILENO);
+
+    posix_spawn(&pid, args[0], &fa, &attr, (char * const *) args, (char * const *) env);
+    posix_spawnp(&pid, args[0], &fa, &attr, (char * const *) args, (char * const *) env);
+
+    posix_spawn_file_actions_destroy(&fa);
+    posix_spawnattr_destroy(&attr);
+
+    return 0;
+}
+" HAVE_POSIX_SPAWN)
+  if(HAVE_POSIX_SPAWN)
+    sdl_glob_sources("${SDL3_SOURCE_DIR}/src/process/posix/*.c")
+    set(SDL_PROCESS_POSIX 1)
+    set(HAVE_SDL_PROCESS TRUE)
+  endif()
+endif()
+
 # Platform-independent options
 
 if(SDL_VIDEO)
@@ -2949,6 +2998,10 @@ if(NOT HAVE_SDL_DIALOG)
   set(SDL_DIALOG_DUMMY 1)
   sdl_sources(${SDL3_SOURCE_DIR}/src/dialog/dummy/SDL_dummydialog.c)
 endif()
+if(NOT HAVE_SDL_PROCESS)
+  set(SDL_PROCESS_DUMMY 1)
+  sdl_glob_sources(${SDL3_SOURCE_DIR}/src/process/dummy/*.c)
+endif()
 if(NOT HAVE_CAMERA)
   set(SDL_CAMERA_DRIVER_DUMMY 1)
   sdl_glob_sources("${SDL3_SOURCE_DIR}/src/camera/dummy/*.c")

VisualC-GDK/SDL/SDL.vcxproj

@@ -364,6 +364,8 @@
     <ClInclude Include="..\..\include\SDL3\SDL_platform.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_platform_defines.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_power.h" />
+    <ClInclude Include="..\..\include\SDL3\SDL_process.h" />
+    <ClInclude Include="..\..\include\SDL3\SDL_properties.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_rect.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_render.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_revision.h" />
@@ -754,6 +756,9 @@
     <ClCompile Include="..\..\src\misc\windows\SDL_sysurl.c" />
     <ClCompile Include="..\..\src\power\SDL_power.c" />
     <ClCompile Include="..\..\src\power\windows\SDL_syspower.c" />
+    <ClCompile Include="..\..\src\process\SDL_process.c" />
+    <ClCompile Include="..\..\src\process\dummy\SDL_dummyprocess.c" />
+    <ClCompile Include="..\..\src\process\windows\SDL_windowsprocess.c" />
     <ClCompile Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.c" />
     <ClCompile Include="..\..\src\render\direct3d12\SDL_render_d3d12.c">
       <CompileAs Condition="'$(Configuration)|$(Platform)'=='Debug|Gaming.Xbox.Scarlett.x64'">CompileAsCpp</CompileAs>

VisualC-GDK/SDL/SDL.vcxproj.filters

@@ -126,6 +126,9 @@
     <ClCompile Include="..\..\src\misc\SDL_url.c" />
     <ClCompile Include="..\..\src\misc\windows\SDL_sysurl.c" />
     <ClCompile Include="..\..\src\power\SDL_power.c" />
+    <ClCompile Include="..\..\src\process\SDL_process.c" />
+    <ClCompile Include="..\..\src\process\dummy\SDL_dummyprocess.c" />
+    <ClCompile Include="..\..\src\process\windows\SDL_windowsprocess.c" />
     <ClCompile Include="..\..\src\power\windows\SDL_syspower.c" />
     <ClCompile Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.c" />
     <ClCompile Include="..\..\src\render\direct3d12\SDL_render_d3d12.c" />
@@ -283,6 +286,8 @@
     <ClInclude Include="..\..\include\SDL3\SDL_platform.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_platform_defines.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_power.h" />
+    <ClInclude Include="..\..\include\SDL3\SDL_process.h" />
+    <ClInclude Include="..\..\include\SDL3\SDL_properties.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_rect.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_render.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_revision.h" />

VisualC/SDL/SDL.vcxproj

@@ -284,6 +284,7 @@
     <ClInclude Include="..\..\include\SDL3\SDL_platform.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_platform_defines.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_power.h" />
+    <ClInclude Include="..\..\include\SDL3\SDL_process.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_properties.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_rect.h" />
     <ClInclude Include="..\..\include\SDL3\SDL_render.h" />
@@ -615,6 +616,8 @@
     <ClCompile Include="..\..\src\misc\windows\SDL_sysurl.c" />
     <ClCompile Include="..\..\src\power\SDL_power.c" />
     <ClCompile Include="..\..\src\power\windows\SDL_syspower.c" />
+    <ClCompile Include="..\..\src\process\SDL_process.c" />
+    <ClCompile Include="..\..\src\process\windows\SDL_windowsprocess.c" />
     <ClCompile Include="..\..\src\render\direct3d11\SDL_shaders_d3d11.c" />
     <ClCompile Include="..\..\src\render\direct3d12\SDL_render_d3d12.c" />
     <ClCompile Include="..\..\src\render\direct3d12\SDL_shaders_d3d12.c" />

VisualC/SDL/SDL.vcxproj.filters

@@ -348,6 +348,9 @@
     <ClInclude Include="..\..\include\SDL3\SDL_power.h">
       <Filter>API Headers</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\include\SDL3\SDL_process.h">
+      <Filter>API Headers</Filter>
+    </ClInclude>
     <ClInclude Include="..\..\include\SDL3\SDL_properties.h">
       <Filter>API Headers</Filter>
     </ClInclude>
@@ -1538,10 +1541,16 @@
     <ClCompile Include="..\..\src\power\SDL_power.c">
       <Filter>power</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\SDL_log.c" />
     <ClCompile Include="..\..\src\power\windows\SDL_syspower.c">
       <Filter>power\windows</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\process\SDL_process.c">
+      <Filter>process</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\src\process\windows\SDL_windowsprocess.c">
+      <Filter>process\windows</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\src\SDL_log.c" />
     <ClCompile Include="..\..\src\render\direct3d12\SDL_render_d3d12.c">
       <Filter>render\direct3d12</Filter>
     </ClCompile>

Xcode/SDL/SDL.xcodeproj/project.pbxproj

@@ -457,6 +457,11 @@
 		F3B38CD7296E2E52005DA6D3 /* SDL_init.h in Headers */ = {isa = PBXBuildFile; fileRef = F3B38CCC296E2E52005DA6D3 /* SDL_init.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		F3B38CDB296E2E52005DA6D3 /* SDL_oldnames.h in Headers */ = {isa = PBXBuildFile; fileRef = F3B38CCD296E2E52005DA6D3 /* SDL_oldnames.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		F3B38CDF296E2E52005DA6D3 /* SDL_intrin.h in Headers */ = {isa = PBXBuildFile; fileRef = F3B38CCE296E2E52005DA6D3 /* SDL_intrin.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		F3B439482C93595900792030 /* SDL_process.h in Headers */ = {isa = PBXBuildFile; fileRef = F3B439472C93595900792030 /* SDL_process.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		F3B439512C935C2400792030 /* SDL_dummyprocess.c in Sources */ = {isa = PBXBuildFile; fileRef = F3B439502C935C2400792030 /* SDL_dummyprocess.c */; };
+		F3B439532C935C2C00792030 /* SDL_posixprocess.c in Sources */ = {isa = PBXBuildFile; fileRef = F3B439522C935C2C00792030 /* SDL_posixprocess.c */; };
+		F3B439562C937DAB00792030 /* SDL_process.c in Sources */ = {isa = PBXBuildFile; fileRef = F3B439542C937DAB00792030 /* SDL_process.c */; };
+		F3B439572C937DAB00792030 /* SDL_sysprocess.h in Headers */ = {isa = PBXBuildFile; fileRef = F3B439552C937DAB00792030 /* SDL_sysprocess.h */; };
 		F3C2CB222C5DDDB2004D7998 /* SDL_categories_c.h in Headers */ = {isa = PBXBuildFile; fileRef = F3C2CB202C5DDDB2004D7998 /* SDL_categories_c.h */; };
 		F3C2CB232C5DDDB2004D7998 /* SDL_categories.c in Sources */ = {isa = PBXBuildFile; fileRef = F3C2CB212C5DDDB2004D7998 /* SDL_categories.c */; };
 		F3D60A8328C16A1900788A3A /* SDL_hidapi_wii.c in Sources */ = {isa = PBXBuildFile; fileRef = F3D60A8228C16A1800788A3A /* SDL_hidapi_wii.c */; };
@@ -1023,6 +1028,11 @@
 		F3B38CCC296E2E52005DA6D3 /* SDL_init.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SDL_init.h; path = SDL3/SDL_init.h; sourceTree = "<group>"; };
 		F3B38CCD296E2E52005DA6D3 /* SDL_oldnames.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SDL_oldnames.h; path = SDL3/SDL_oldnames.h; sourceTree = "<group>"; };
 		F3B38CCE296E2E52005DA6D3 /* SDL_intrin.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SDL_intrin.h; path = SDL3/SDL_intrin.h; sourceTree = "<group>"; };
+		F3B439472C93595900792030 /* SDL_process.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SDL_process.h; path = SDL3/SDL_process.h; sourceTree = "<group>"; };
+		F3B439502C935C2400792030 /* SDL_dummyprocess.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SDL_dummyprocess.c; sourceTree = "<group>"; };
+		F3B439522C935C2C00792030 /* SDL_posixprocess.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SDL_posixprocess.c; sourceTree = "<group>"; };
+		F3B439542C937DAB00792030 /* SDL_process.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SDL_process.c; sourceTree = "<group>"; };
+		F3B439552C937DAB00792030 /* SDL_sysprocess.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SDL_sysprocess.h; sourceTree = "<group>"; };
 		F3C2CB202C5DDDB2004D7998 /* SDL_categories_c.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SDL_categories_c.h; sourceTree = "<group>"; };
 		F3C2CB212C5DDDB2004D7998 /* SDL_categories.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SDL_categories.c; sourceTree = "<group>"; };
 		F3D60A8228C16A1800788A3A /* SDL_hidapi_wii.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SDL_hidapi_wii.c; sourceTree = "<group>"; };
@@ -1265,6 +1275,7 @@
 				F3B38CCB296E2E52005DA6D3 /* SDL_platform_defines.h */,
 				F3F7D8AB2933074900816151 /* SDL_platform.h */,
 				F3F7D8DB2933074D00816151 /* SDL_power.h */,
+				F3B439472C93595900792030 /* SDL_process.h */,
 				F3E5A6EC2AD5E10800293D83 /* SDL_properties.h */,
 				F3F7D8E22933074D00816151 /* SDL_rect.h */,
 				F3F7D8DE2933074D00816151 /* SDL_render.h */,
@@ -1338,6 +1349,7 @@
 				000082EF09C89B62BD840000 /* main */,
 				5616CA47252BB278005D5928 /* misc */,
 				A7D8A7DF23E2513F00DCD162 /* power */,
+				F3B439492C93597500792030 /* process */,
 				A7D8A8DA23E2514000DCD162 /* render */,
 				A7D8A57623E2513D00DCD162 /* sensor */,
 				A7D8A8D223E2514000DCD162 /* stdlib */,
@@ -2368,6 +2380,33 @@
 			path = ios;
 			sourceTree = "<group>";
 		};
+		F3B439492C93597500792030 /* process */ = {
+			isa = PBXGroup;
+			children = (
+				F3B4394A2C93599900792030 /* dummy */,
+				F3B4394B2C9359A500792030 /* posix */,
+				F3B439542C937DAB00792030 /* SDL_process.c */,
+				F3B439552C937DAB00792030 /* SDL_sysprocess.h */,
+			);
+			path = process;
+			sourceTree = "<group>";
+		};
+		F3B4394A2C93599900792030 /* dummy */ = {
+			isa = PBXGroup;
+			children = (
+				F3B439502C935C2400792030 /* SDL_dummyprocess.c */,
+			);
+			path = dummy;
+			sourceTree = "<group>";
+		};
+		F3B4394B2C9359A500792030 /* posix */ = {
+			isa = PBXGroup;
+			children = (
+				F3B439522C935C2C00792030 /* SDL_posixprocess.c */,
+			);
+			path = posix;
+			sourceTree = "<group>";
+		};
 		F59C70FC00D5CB5801000001 /* pkg-support */ = {
 			isa = PBXGroup;
 			children = (
@@ -2442,6 +2481,7 @@
 				F3F7D9B92933074E00816151 /* SDL_cpuinfo.h in Headers */,
 				A7D8B98023E2514400DCD162 /* SDL_d3dmath.h in Headers */,
 				A7D8B8A223E2514400DCD162 /* SDL_diskaudio.h in Headers */,
+				F3B439482C93595900792030 /* SDL_process.h in Headers */,
 				A7D8BB3F23E2514500DCD162 /* SDL_displayevents_c.h in Headers */,
 				A7D8BA1923E2514400DCD162 /* SDL_draw.h in Headers */,
 				F3C2CB222C5DDDB2004D7998 /* SDL_categories_c.h in Headers */,
@@ -2572,6 +2612,7 @@
 				A7D8AC3F23E2514100DCD162 /* SDL_sysvideo.h in Headers */,
 				F3F7D9792933074E00816151 /* SDL_thread.h in Headers */,
 				A7D8B3EC23E2514300DCD162 /* SDL_thread_c.h in Headers */,
+				F3B439572C937DAB00792030 /* SDL_sysprocess.h in Headers */,
 				E4F257912C81903800FCEAFC /* Metal_Blit.h in Headers */,
 				F3F7D90D2933074E00816151 /* SDL_timer.h in Headers */,
 				A7D8AB3123E2514100DCD162 /* SDL_timer_c.h in Headers */,
@@ -2800,6 +2841,7 @@
 				A7D8B9F523E2514400DCD162 /* SDL_rotate.c in Sources */,
 				A7D8BBE323E2574800DCD162 /* SDL_uikitvideo.m in Sources */,
 				5616CA4E252BB2A6005D5928 /* SDL_sysurl.m in Sources */,
+				F3B439562C937DAB00792030 /* SDL_process.c in Sources */,
 				A7D8A97523E2514000DCD162 /* SDL_coremotionsensor.m in Sources */,
 				F382071D284F362F004DD584 /* SDL_guid.c in Sources */,
 				A7D8BB8D23E2514500DCD162 /* SDL_touch.c in Sources */,
@@ -2862,6 +2904,7 @@
 				A7D8BA8B23E2514400DCD162 /* s_sin.c in Sources */,
 				F3F528CE2C29E1C300E6CC26 /* s_modf.c in Sources */,
 				A7D8BBEB23E2574800DCD162 /* SDL_uikitwindow.m in Sources */,
+				F3B439532C935C2C00792030 /* SDL_posixprocess.c in Sources */,
 				F395BF6525633B2400942BFF /* SDL_crc32.c in Sources */,
 				A7D8B5E723E2514300DCD162 /* SDL_power.c in Sources */,
 				A7D8AED623E2514100DCD162 /* SDL_cocoakeyboard.m in Sources */,
@@ -2905,6 +2948,7 @@
 				A7D8BADF23E2514500DCD162 /* e_fmod.c in Sources */,
 				A7D8B5CF23E2514300DCD162 /* SDL_syspower.m in Sources */,
 				A7D8BAEB23E2514500DCD162 /* e_log10.c in Sources */,
+				F3B439512C935C2400792030 /* SDL_dummyprocess.c in Sources */,
 				A7D8B76423E2514300DCD162 /* SDL_mixer.c in Sources */,
 				A7D8BB5723E2514500DCD162 /* SDL_events.c in Sources */,
 				A7D8ADE623E2514100DCD162 /* SDL_blit_0.c in Sources */,

include/SDL3/SDL.h

@@ -65,6 +65,7 @@
 #include <SDL3/SDL_pixels.h>
 #include <SDL3/SDL_platform.h>
 #include <SDL3/SDL_power.h>
+#include <SDL3/SDL_process.h>
 #include <SDL3/SDL_properties.h>
 #include <SDL3/SDL_rect.h>
 #include <SDL3/SDL_render.h>

include/SDL3/SDL_iostream.h

@@ -133,6 +133,17 @@ typedef struct SDL_IOStreamInterface
      */
     size_t (SDLCALL *write)(void *userdata, const void *ptr, size_t size, SDL_IOStatus *status);
 
+    /**
+     *  If the stream is buffering, make sure the data is written out.
+     *
+     *  On failure, you should set `*status` to a value from the
+     *  SDL_IOStatus enum. You do not have to explicitly set this on
+     *  a successful flush.
+     *
+     *  \return SDL_TRUE if successful or SDL_FALSE on write error when flushing data.
+     */
+    SDL_bool (SDLCALL *flush)(void *userdata, SDL_IOStatus *status);
+
     /**
      *  Close and free any allocated resources.
      *
@@ -152,8 +163,8 @@ typedef struct SDL_IOStreamInterface
  * the code using this interface should be updated to handle the old version.
  */
 SDL_COMPILE_TIME_ASSERT(SDL_IOStreamInterface_SIZE,
-    (sizeof(void *) == 4 && sizeof(SDL_IOStreamInterface) == 24) ||
-    (sizeof(void *) == 8 && sizeof(SDL_IOStreamInterface) == 48));
+    (sizeof(void *) == 4 && sizeof(SDL_IOStreamInterface) == 28) ||
+    (sizeof(void *) == 8 && sizeof(SDL_IOStreamInterface) == 56));
 
 /**
  * The read/write operation structure.
@@ -233,6 +244,7 @@ typedef struct SDL_IOStream SDL_IOStream;
  *   than your app, trying to use this pointer will almost certainly result in
  *   a crash! This is mostly a problem on Windows; make sure you build SDL and
  *   your app with the same compiler and settings to avoid it.
+ * - `SDL_PROP_IOSTREAM_FILE_DESCRIPTOR_NUMBER`: a file descriptor that this SDL_IOStream is using to access the filesystem.
  * - `SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER`: a pointer, that can be cast
  *   to an Android NDK `AAsset *`, that this SDL_IOStream is using to access
  *   the filesystem. If SDL used some other method to access the filesystem,
@@ -247,6 +259,7 @@ typedef struct SDL_IOStream SDL_IOStream;
  * \since This function is available since SDL 3.0.0.
  *
  * \sa SDL_CloseIO
+ * \sa SDL_FlushIO
  * \sa SDL_ReadIO
  * \sa SDL_SeekIO
  * \sa SDL_TellIO
@@ -256,6 +269,7 @@ extern SDL_DECLSPEC SDL_IOStream * SDLCALL SDL_IOFromFile(const char *file, cons
 
 #define SDL_PROP_IOSTREAM_WINDOWS_HANDLE_POINTER    "SDL.iostream.windows.handle"
 #define SDL_PROP_IOSTREAM_STDIO_FILE_POINTER        "SDL.iostream.stdio.file"
+#define SDL_PROP_IOSTREAM_FILE_DESCRIPTOR_NUMBER    "SDL.iostream.file_descriptor"
 #define SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER    "SDL.iostream.android.aasset"
 
 /**
@@ -282,6 +296,7 @@ extern SDL_DECLSPEC SDL_IOStream * SDLCALL SDL_IOFromFile(const char *file, cons
  *
  * \sa SDL_IOFromConstMem
  * \sa SDL_CloseIO
+ * \sa SDL_FlushIO
  * \sa SDL_ReadIO
  * \sa SDL_SeekIO
  * \sa SDL_TellIO
@@ -465,8 +480,7 @@ extern SDL_DECLSPEC Sint64 SDLCALL SDL_GetIOSize(SDL_IOStream *context);
  *               negative.
  * \param whence any of `SDL_IO_SEEK_SET`, `SDL_IO_SEEK_CUR`,
  *               `SDL_IO_SEEK_END`.
- * \returns the final offset in the data stream after the seek or a negative
- *          error code on failure; call SDL_GetError() for more information.
+ * \returns the final offset in the data stream after the seek or -1 on failure; call SDL_GetError() for more information.
  *
  * \since This function is available since SDL 3.0.0.
  *
@@ -539,6 +553,7 @@ extern SDL_DECLSPEC size_t SDLCALL SDL_ReadIO(SDL_IOStream *context, void *ptr,
  * \sa SDL_IOprintf
  * \sa SDL_ReadIO
  * \sa SDL_SeekIO
+ * \sa SDL_FlushIO
  * \sa SDL_GetIOStatus
  */
 extern SDL_DECLSPEC size_t SDLCALL SDL_WriteIO(SDL_IOStream *context, const void *ptr, size_t size);
@@ -580,6 +595,22 @@ extern SDL_DECLSPEC size_t SDLCALL SDL_IOprintf(SDL_IOStream *context, SDL_PRINT
  */
 extern SDL_DECLSPEC size_t SDLCALL SDL_IOvprintf(SDL_IOStream *context, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2);
 
+/**
+ * Flush any buffered data in the stream.
+ *
+ * This function makes sure that any buffered data is written to the stream. Normally this isn't necessary but if the stream is a pipe or socket it guarantees that any pending data is sent.
+ *
+ * \param context SDL_IOStream structure to flush.
+ * \returns SDL_TRUE on success or SDL_FALSE on failure; call SDL_GetError()
+ *          for more information.
+ *
+ * \since This function is available since SDL 3.0.0.
+ *
+ * \sa SDL_OpenIO
+ * \sa SDL_WriteIO
+ */
+extern SDL_DECLSPEC SDL_bool SDLCALL SDL_FlushIO(SDL_IOStream *context);
+
 /**
  * Load all the data from an SDL data stream.
  *
@@ -590,7 +621,7 @@ extern SDL_DECLSPEC size_t SDLCALL SDL_IOvprintf(SDL_IOStream *context, SDL_PRIN
  * The data should be freed with SDL_free().
  *
  * \param src the SDL_IOStream to read all available data from.
- * \param datasize if not NULL, will store the number of bytes read.
+ * \param datasize a pointer filled in with the number of bytes read, may be NULL.
  * \param closeio if SDL_TRUE, calls SDL_CloseIO() on `src` before returning,
  *                even in the case of an error.
  * \returns the data or NULL on failure; call SDL_GetError() for more