X11 has a so-called primary selection, which you can use by marking text and middle-clicking elsewhere to copy the marked text.
There are 3 new API functions in `SDL_clipboard.h`, which work exactly like their clipboard equivalents.
## Test Instructions
* Run the tests (just a copy of the clipboard tests): `$ ./test/testautomation --filter Clipboard`
* Build and run this small application:
<details>
```C
#include <SDL.h>
#include <unistd.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
void print_error(const char *where)
{
const char *errstr = SDL_GetError();
if (errstr == NULL || errstr[0] == '\0')
return;
fprintf(stderr, "SDL Error after '%s': %s\n", where, errstr);
SDL_ClearError();
}
int main()
{
char text_buf[256];
srand(time(NULL));
SDL_Init(SDL_INIT_VIDEO);
print_error("SDL_INIT()");
SDL_Window *window = SDL_CreateWindow("Primary Selection Test", SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED, 400, 400, SDL_WINDOW_SHOWN);
print_error("SDL_CreateWindow()");
SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
print_error("SDL_CreateRenderer()");
bool quit = false;
unsigned int do_render = 0;
while (!quit) {
SDL_Event event;
while (SDL_PollEvent(&event)) {
print_error("SDL_PollEvent()");
switch (event.type) {
case SDL_QUIT: {
quit = true;
break;
} case SDL_KEYDOWN: {
switch (event.key.keysym.sym) {
case SDLK_ESCAPE:
case SDLK_q:
quit = true;
break;
case SDLK_c:
snprintf(text_buf, sizeof(text_buf), "foo%d", rand());
SDL_SetClipboardText(text_buf);
print_error("SDL_SetClipboardText()");
printf("clipboard: set_to=\"%s\"\n", text_buf);
break;
case SDLK_v: {
printf("clipboard: has=%d, ", SDL_HasClipboardText());
print_error("SDL_HasClipboardText()");
char *text = SDL_GetClipboardText();
print_error("SDL_GetClipboardText()");
printf("text=\"%s\"\n", text);
SDL_free(text);
break;
} case SDLK_d:
snprintf(text_buf, sizeof(text_buf), "bar%d", rand());
SDL_SetPrimarySelectionText(text_buf);
print_error("SDL_SetPrimarySelectionText()");
printf("primselec: set_to=\"%s\"\n", text_buf);
break;
case SDLK_f: {
printf("primselec: has=%d, ", SDL_HasPrimarySelectionText());
print_error("SDL_HasPrimarySelectionText()");
char *text = SDL_GetPrimarySelectionText();
print_error("SDL_GetPrimarySelectionText()");
printf("text=\"%s\"\n", text);
SDL_free(text);
break;
} default:
break;
}
break;
} default: {
break;
}}
}
// create less noise with WAYLAND_DEBUG=1
if (do_render == 0) {
SDL_RenderPresent(renderer);
print_error("SDL_RenderPresent()");
}
do_render += 1;
usleep(12000);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
print_error("quit");
return 0;
}
```
</details>
* Use c,v,d,f to get and set the clipboard and primary selection.
* Mark text and middle-click also in other applications.
* For wayland under x:
* `$ mutter --wayland --no-x11 --nested`
* `$ XDG_SESSION_TYPE=wayland SDL_VIDEODRIVER=wayland ./<path_to_test_appl_binary>`
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
