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ADD: MuPDF v1.26.7: the MuPDF source as downloaded by a default build of PyMuPDF 1.26.4. The directory name has changed: no version number in the expanded directory now.
author Franz Glasner <fzglas.hg@dom66.de>
date Mon, 15 Sep 2025 11:43:07 +0200
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1:1d09e1dec1d9 2:b50eed0cc0ef
1 <!DOCTYPE html>
2 <html>
3 <head>
4 <link href="style.css" rel="stylesheet">
5 <title>MuJS Examples</title>
6 </head>
7
8 <body>
9
10 <header>
11 <h1>MuJS Examples</h1>
12 </header>
13
14 <nav>
15 <a href="introduction.html">Introduction</a>
16 <a href="reference.html">Reference</a>
17 <a href="examples.html">Examples</a>
18 <a href="license.html">License</a>
19 <a href="http://git.ghostscript.com/?p=mujs.git;a=summary">Source</a>
20 <a href="https://bugs.ghostscript.com/">Bugs</a>
21 </nav>
22
23 <article>
24
25 <h2>A stand-alone interpreter</h2>
26
27 <pre>
28 #include &lt;stdio.h&gt;
29 #include &lt;mujs.h&gt;
30
31 int main(int argc, char **argv)
32 {
33 char line[256];
34 js_State *J = js_newstate(NULL, NULL, JS_STRICT);
35 while (fgets(line, sizeof line, stdin))
36 js_dostring(J, line);
37 js_freestate(J);
38 }
39 </pre>
40
41 <h2>Hello, world!</h2>
42
43 <pre>
44 #include &lt;stdio.h&gt;
45 #include &lt;mujs.h&gt;
46
47 static void hello(js_State *J)
48 {
49 const char *name = js_tostring(J, 1);
50 printf("Hello, %s!\n", name);
51 js_pushundefined(J);
52 }
53
54 int main(int argc, char **argv)
55 {
56 js_State *J = js_newstate(NULL, NULL, JS_STRICT);
57
58 js_newcfunction(J, hello, "hello", 1);
59 js_setglobal(J, "hello");
60
61 js_dostring(J, "hello('world');");
62
63 js_freestate(J);
64 }
65 </pre>
66
67 <h2>Configuration file</h2>
68
69 <pre>
70 js_dofile(J, "config.js")
71
72 js_getglobal(J, "foo");
73 foo = js_tonumber(J, -1);
74 js_pop(J, 1);
75 </pre>
76
77 <h2>Object manipulation</h2>
78
79 <pre>
80 // t = { foo: 42, bar: true }
81
82 js_newobject(J);
83 {
84 js_pushnumber(J, 42);
85 js_setproperty(J, -2, "foo");
86 js_pushboolean(J, 1);
87 js_setproperty(J, -2, "bar");
88 }
89 js_setglobal(J, "t");
90 </pre>
91
92 <h2>Callbacks from C to JS (by name)</h2>
93
94 <pre>
95 static int call_callback(js_State *J, const char *arg1, int arg2)
96 {
97 int result;
98
99 /* Find the function to call. */
100 js_getglobal(J, "my_callback");
101
102 /* Push arguments to function. */
103 js_pushnull(J); /* the 'this' object to use */
104 js_pushstring(J, arg1);
105 js_pushnumber(J, arg2);
106
107 /* Call function and check for exceptions. */
108 if (js_pcall(J, 2)) {
109 fprintf(stderr, "an exception occurred in the javascript callback\n");
110 js_pop(J, 1);
111 return -1;
112 }
113
114 /* Retrieve return value. */
115 result = js_tonumber(J, -1);
116 js_pop(J, 1);
117
118 return result;
119 }
120 </pre>
121
122 <h2>Callbacks from C to JS</h2>
123
124 <pre>
125 const char *handle = NULL; /* handle to stowed away js function */
126
127 static void set_callback(js_State *J)
128 {
129 if (handle)
130 js_unref(J, handle); /* delete old function */
131 js_copy(J, 1);
132 handle = js_ref(J); /* stow the js function in the registry */
133 }
134
135 static void call_callback(js_State *J, int arg1, int arg2)
136 {
137 js_getregistry(J, handle); /* retrieve the js function from the registry */
138 js_pushnull(J);
139 js_pushnumber(J, arg1);
140 js_pushnumber(J, arg2);
141 js_pcall(J, 2);
142 js_pop(J, 1);
143 }
144 </pre>
145
146 <h2>Complete userdata example</h2>
147
148 <pre>
149 #include &lt;stdio.h&gt;
150 #include &lt;mujs.h&gt;
151
152 #define TAG "File"
153
154 static void new_File(js_State *J)
155 {
156 FILE *file;
157
158 if (js_isundefined(J, 1)) {
159 file = stdin;
160 } else {
161 const char *filename = js_tostring(J, 1);
162 file = fopen(filename, "r");
163 if (!file)
164 js_error(J, "cannot open file: '%s'", filename);
165 }
166
167 js_currentfunction(J);
168 js_getproperty(J, -1, "prototype");
169 js_newuserdata(J, TAG, file);
170 }
171
172 static void File_prototype_readByte(js_State *J)
173 {
174 FILE *file = js_touserdata(J, 0, TAG);
175 js_pushnumber(J, getc(file));
176 }
177
178 static void File_prototype_readLine(js_State *J)
179 {
180 char line[256], *s;
181 FILE *file = js_touserdata(J, 0, TAG);
182 s = fgets(line, sizeof line, file);
183 if (s)
184 js_pushstring(J, line);
185 else
186 js_pushnull(J);
187 }
188
189 static void File_prototype_close(js_State *J)
190 {
191 FILE *file = js_touserdata(J, 0, TAG);
192 fclose(file);
193 js_pushundefined(J);
194 }
195
196 void initfile(js_State *J)
197 {
198 js_getglobal(J, "Object");
199 js_getproperty(J, -1, "prototype"); // File.prototype.[[Prototype]] = Object.prototype
200 js_newuserdata(J, TAG, stdin); // File.prototype.[[Userdata]] = stdin
201 {
202 js_newcfunction(J, File_prototype_readByte, "File.prototype.readByte", 0);
203 js_defproperty(J, -2, "readByte", JS_DONTENUM);
204
205 js_newcfunction(J, File_prototype_readLine, "File.prototype.readLine", 0);
206 js_defproperty(J, -2, "readLine", JS_DONTENUM);
207
208 js_newcfunction(J, File_prototype_close, "File.prototype.close", 0);
209 js_defproperty(J, -2, "close", JS_DONTENUM);
210 }
211 js_newcconstructor(J, new_File, new_File, "File", 1);
212 js_defglobal(J, "File", JS_DONTENUM);
213 }
214 </pre>
215
216 </article>
217
218 <footer>
219 <a href="http://artifex.com"><img src="artifex-logo.png" align="right"></a>
220 Copyright &copy; 2013-2017 Artifex Software Inc.
221 </footer>
222
223 </body>
224 </html>