真奇怪啊。关于LINUX剪贴板的C代码，网上完全找不到。找到的都是一些SHELL命令。
经过千辛万苦，自己理解，终于找到一个代码范例。
https://github.com/exebook/x11clipboard
https://stackoverflow.com/questions/27378318/c-get-string-from-clipboard-on-linux
为了方便他人，提供代码如下（初步测试表明，图片取不到数据）：
标准情况：
// gcc -o xclipget xclipget.c -lX11 #include <stdio.h> #include <limits.h> #include <X11/Xlib.h> Bool PrintSelection(Display *display, Window window, const char *bufname, const char *fmtname) { char *result; unsigned long ressize, restail; int resbits; Atom bufid = XInternAtom(display, bufname, False), fmtid = XInternAtom(display, fmtname, False), propid = XInternAtom(display, "XSEL_DATA", False), incrid = XInternAtom(display, "INCR", False); XEvent event; XConvertSelection(display, bufid, fmtid, propid, window, CurrentTime); do { XNextEvent(display, &event); } while (event.type != SelectionNotify || event.xselection.selection != bufid); if (event.xselection.property) { XGetWindowProperty(display, window, propid, 0, LONG_MAX/4, False, AnyPropertyType, &fmtid, &resbits, &ressize, &restail, (unsigned char**)&result); if (fmtid == incrid) printf("Buffer is too large and INCR reading is not implemented yet.\n"); else printf("%.*s", (int)ressize, result); XFree(result); return True; } else // request failed, e.g. owner can't convert to the target format return False; } int main() { Display *display = XOpenDisplay(NULL); unsigned long color = BlackPixel(display, DefaultScreen(display)); Window window = XCreateSimpleWindow(display, DefaultRootWindow(display), 0,0, 1,1, 0, color, color); Bool result = PrintSelection(display, window, "CLIPBOARD", "UTF8_STRING") || PrintSelection(display, window, "CLIPBOARD", "STRING"); XDestroyWindow(display, window); XCloseDisplay(display); return !result; }
超大内存情况
// gcc -o xclipget xclipget.c -lX11 #include <stdio.h> #include <limits.h> #include <X11/Xlib.h> Bool PrintSelection(Display *display, Window window, const char *bufname, const char *fmtname) { char *result; unsigned long ressize, restail; int resbits; Atom bufid = XInternAtom(display, bufname, False), fmtid = XInternAtom(display, fmtname, False), propid = XInternAtom(display, "XSEL_DATA", False), incrid = XInternAtom(display, "INCR", False); XEvent event; XSelectInput (display, window, PropertyChangeMask); XConvertSelection(display, bufid, fmtid, propid, window, CurrentTime); do { XNextEvent(display, &event); } while (event.type != SelectionNotify || event.xselection.selection != bufid); if (event.xselection.property) { XGetWindowProperty(display, window, propid, 0, LONG_MAX/4, True, AnyPropertyType, &fmtid, &resbits, &ressize, &restail, (unsigned char**)&result); if (fmtid != incrid) printf("%.*s", (int)ressize, result); XFree(result); if (fmtid == incrid) do { do { XNextEvent(display, &event); } while (event.type != PropertyNotify || event.xproperty.atom != propid || event.xproperty.state != PropertyNewValue); XGetWindowProperty(display, window, propid, 0, LONG_MAX/4, True, AnyPropertyType, &fmtid, &resbits, &ressize, &restail, (unsigned char**)&result); printf("%.*s", (int)ressize, result); XFree(result); } while (ressize > 0); return True; } else // request failed, e.g. owner can't convert to the target format return False; } int main() { Display *display = XOpenDisplay(NULL); unsigned long color = BlackPixel(display, DefaultScreen(display)); Window window = XCreateSimpleWindow(display, DefaultRootWindow(display), 0,0, 1,1, 0, color, color); Bool result = PrintSelection(display, window, "CLIPBOARD", "UTF8_STRING") || PrintSelection(display, window, "CLIPBOARD", "STRING"); XDestroyWindow(display, window); XCloseDisplay(display); return !result; }
