Linux桌面实用工具

第一个就是大名鼎鼎的jump-or-exec，貌似我的代码是从不知道那个地方抄来的，作者莫怪。

#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xatom.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

int
main(int argc, char* argv[])
{
    if (argc < 3) {
        fprintf(stderr, "Usage: %s resource_name start_command\n\n", argv[0]);
        fprintf(stderr, "resource_name: the window's X resource name.\n");
        fprintf(stderr, "start_command: the command to start a new window.\n");
        return 0;
    }

    const char *res_class = argv[1];
    printf("The inputed resource name is %s.\n", res_class);

    Display *display = XOpenDisplay(NULL);
    if (!display) {
        fprintf(stderr, "This program should be run within X environment.\n");
        return 1;
    }
    Window root = DefaultRootWindow(display);
    Window *windows = NULL;
    unsigned long win_num, i = 0;
    Atom actual_return_type;
    int actual_format_return;
    unsigned long bytes;
    XGetWindowProperty(display,
                       root,
                       XInternAtom(display, "_NET_CLIENT_LIST", False),
                       0,
                       1024,
                       False,
                       XA_WINDOW,
                       &actual_return_type,
                       &actual_format_return,
                       &win_num,
                       &bytes,
                       (unsigned char**) &windows);
    printf("Found %d windows.\n", win_num);

    for (; i < win_num; ++i) {
        XClassHint hint;
        memset(&hint, 0, sizeof(hint));
        XGetClassHint(display, windows[i], &hint);
        printf("%s\n", hint.res_class);
        if (hint.res_class) {
            if (strcasecmp(res_class, hint.res_class) == 0) {
                printf("Found!!!\n");
                XMapRaised(display, windows[i]);
                XCloseDisplay(display);
                return 0;
            }
        }
    }

    /* Reach here means the window with the name was not found. */
    system(argv[2]);

    if (windows)
        XFree(windows);
    return 0;
}

用法：

$ jump-or-exec gecko firefox

其中第一个参数为窗口的class名称，可用xprop命令查看，记得是WM_CLASS属性中的第二个字符串；第二个参数为启动该程序的命令。

第二个工具就是用来控制当前窗口的透明度的，当然前提就是你的WM要支持真透明。比如我用的Xfce4，再用之前就要先开启设置->窗口管理器调整->混合设置->允许混合显示。另外你用的xorg也要支持，并且在你的xorg.conf文件中要有这么一段：

Section "Extensions"
    Option "Composite" "true"
EndSection

代码如下：

#include <X11/Xlib.h>
#include <X11/Xlibint.h>
#include <X11/Xutil.h>
#include <X11/Xatom.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

#define OPACITY 0xffff

int
main(int argc, char* argv[])
{
    if (argc < 2) {
        fprintf(stderr, "Usage: %s step\n\n", argv[0]);
        fprintf(stderr, "step: to in(de)crease opacity of current window.\n");
        fprintf(stderr, "      Maybe negative.\n");
        return 0;
    }

    int step = atoi(argv[1]);

    Display *display = XOpenDisplay(NULL);
    if (!display) {
        fprintf(stderr, "This program should be run within X environment.\n");
        return 1;
    }

    Atom opacity_atom = XInternAtom(display, "_NET_WM_WINDOW_OPACITY", 0);

    Atom actual;
    int result, format;
    unsigned long n, left;
    unsigned char *data;

    result = XGetWindowProperty(display, DefaultRootWindow(display),
                                XInternAtom(display, "_NET_ACTIVE_WINDOW", 0),
                                0L, 1L, False, XA_WINDOW, &actual, &format,
                                &n, &left, &data);
    if (result != Success || !n || !data)
        return 0;
    Window active = *((Window *)data);
    XClassHint hint;
    memset(&hint, 0, sizeof(XClassHint));
    XGetClassHint(display, active, &hint);
    printf("resource name: %s\n", hint.res_name);

    result = XGetWindowProperty(display, active, opacity_atom,
                                0L, 1L, False, XA_CARDINAL, &actual, &format,
                                &n, &left, &data);
    int opacity = OPACITY;
    if (result == Success && n && data) {
        CARD32 value;
        memcpy(&value, data, sizeof(CARD32));
        XFree(data);
        opacity = value >> 16;
        printf("opacity: %d\n", opacity);
    }
    opacity += OPACITY * step / 100;
    if (opacity < 0)
        opacity = 0;
    if (opacity > OPACITY)
        opacity = OPACITY;
    CARD32 value32 = opacity << 16 | opacity;
    XChangeProperty(display, active, opacity_atom, XA_CARDINAL,
                    32, PropModeReplace, (unsigned char *)&value32, 1);

    XSync(display, False);

    return 0;
}

用法：

$ opacity -20

参数的意思是透明度的调整数值，-20就是“不透明度”-20啦。呃，当初没意识到这个问题，算了。

这两个程序在编译时别忘了加上xlib的编译参数，不知道的话就用pkg-config吧。

嗯，它们的优点就是独立于你所用的WM，配合上xbindkeys这个小软件的话就更加完美了。

嗯，就酱。