Commit | Line | Data |
---|---|---|
920dae64 AT |
1 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> |
2 | <html> | |
3 | <head> | |
4 | <link rel="STYLESHEET" href="lib.css" type='text/css' /> | |
5 | <link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" /> | |
6 | <link rel='start' href='../index.html' title='Python Documentation Index' /> | |
7 | <link rel="first" href="lib.html" title='Python Library Reference' /> | |
8 | <link rel='contents' href='contents.html' title="Contents" /> | |
9 | <link rel='index' href='genindex.html' title='Index' /> | |
10 | <link rel='last' href='about.html' title='About this document...' /> | |
11 | <link rel='help' href='about.html' title='About this document...' /> | |
12 | <link rel="next" href="module-builtin.html" /> | |
13 | <link rel="prev" href="module-site.html" /> | |
14 | <link rel="parent" href="python.html" /> | |
15 | <link rel="next" href="module-builtin.html" /> | |
16 | <meta name='aesop' content='information' /> | |
17 | <title>3.31 user -- User-specific configuration hook</title> | |
18 | </head> | |
19 | <body> | |
20 | <DIV CLASS="navigation"> | |
21 | <div id='top-navigation-panel' xml:id='top-navigation-panel'> | |
22 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
23 | <tr> | |
24 | <td class='online-navigation'><a rel="prev" title="3.30 site " | |
25 | href="module-site.html"><img src='../icons/previous.png' | |
26 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
27 | <td class='online-navigation'><a rel="parent" title="3. Python Runtime Services" | |
28 | href="python.html"><img src='../icons/up.png' | |
29 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
30 | <td class='online-navigation'><a rel="next" title="3.32 __builtin__ " | |
31 | href="module-builtin.html"><img src='../icons/next.png' | |
32 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
33 | <td align="center" width="100%">Python Library Reference</td> | |
34 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
35 | href="contents.html"><img src='../icons/contents.png' | |
36 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
37 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
38 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
39 | <td class='online-navigation'><a rel="index" title="Index" | |
40 | href="genindex.html"><img src='../icons/index.png' | |
41 | border='0' height='32' alt='Index' width='32' /></A></td> | |
42 | </tr></table> | |
43 | <div class='online-navigation'> | |
44 | <b class="navlabel">Previous:</b> | |
45 | <a class="sectref" rel="prev" href="module-site.html">3.30 site </A> | |
46 | <b class="navlabel">Up:</b> | |
47 | <a class="sectref" rel="parent" href="python.html">3. Python Runtime Services</A> | |
48 | <b class="navlabel">Next:</b> | |
49 | <a class="sectref" rel="next" href="module-builtin.html">3.32 __builtin__ </A> | |
50 | </div> | |
51 | <hr /></div> | |
52 | </DIV> | |
53 | <!--End of Navigation Panel--> | |
54 | ||
55 | <H1><A NAME="SECTION0053100000000000000000"> | |
56 | 3.31 <tt class="module">user</tt> -- | |
57 | User-specific configuration hook</A> | |
58 | </H1> | |
59 | ||
60 | <P> | |
61 | <A NAME="module-user"></A> | |
62 | ||
63 | <P> | |
64 | <a id='l2h-808' xml:id='l2h-808'></a><a id='l2h-809' xml:id='l2h-809'></a> | |
65 | <P> | |
66 | As a policy, Python doesn't run user-specified code on startup of | |
67 | Python programs. (Only interactive sessions execute the script | |
68 | specified in the <a class="envvar" id='l2h-811' xml:id='l2h-811'>PYTHONSTARTUP</a> environment variable if it | |
69 | exists). | |
70 | ||
71 | <P> | |
72 | However, some programs or sites may find it convenient to allow users | |
73 | to have a standard customization file, which gets run when a program | |
74 | requests it. This module implements such a mechanism. A program | |
75 | that wishes to use the mechanism must execute the statement | |
76 | ||
77 | <P> | |
78 | <div class="verbatim"><pre> | |
79 | import user | |
80 | </pre></div> | |
81 | ||
82 | <P> | |
83 | The <tt class="module">user</tt> module looks for a file <span class="file">.pythonrc.py</span> in the user's | |
84 | home directory and if it can be opened, executes it (using | |
85 | <tt class="function">execfile()</tt><a id='l2h-810' xml:id='l2h-810'></a>) in its own (the | |
86 | module <tt class="module">user</tt>'s) global namespace. Errors during this phase | |
87 | are not caught; that's up to the program that imports the | |
88 | <tt class="module">user</tt> module, if it wishes. The home directory is assumed to | |
89 | be named by the <a class="envvar" id='l2h-812' xml:id='l2h-812'>HOME</a> environment variable; if this is not set, | |
90 | the current directory is used. | |
91 | ||
92 | <P> | |
93 | The user's <span class="file">.pythonrc.py</span> could conceivably test for | |
94 | <code>sys.version</code> if it wishes to do different things depending on | |
95 | the Python version. | |
96 | ||
97 | <P> | |
98 | A warning to users: be very conservative in what you place in your | |
99 | <span class="file">.pythonrc.py</span> file. Since you don't know which programs will | |
100 | use it, changing the behavior of standard modules or functions is | |
101 | generally not a good idea. | |
102 | ||
103 | <P> | |
104 | A suggestion for programmers who wish to use this mechanism: a simple | |
105 | way to let users specify options for your package is to have them | |
106 | define variables in their <span class="file">.pythonrc.py</span> file that you test in | |
107 | your module. For example, a module <tt class="module">spam</tt> that has a verbosity | |
108 | level can look for a variable <code>user.spam_verbose</code>, as follows: | |
109 | ||
110 | <P> | |
111 | <div class="verbatim"><pre> | |
112 | import user | |
113 | ||
114 | verbose = bool(getattr(user, "spam_verbose", 0)) | |
115 | </pre></div> | |
116 | ||
117 | <P> | |
118 | (The three-argument form of <tt class="function">getattr()</tt> is used in case | |
119 | the user has not defined <code>spam_verbose</code> in their | |
120 | <span class="file">.pythonrc.py</span> file.) | |
121 | ||
122 | <P> | |
123 | Programs with extensive customization needs are better off reading a | |
124 | program-specific customization file. | |
125 | ||
126 | <P> | |
127 | Programs with security or privacy concerns should <em>not</em> import | |
128 | this module; a user can easily break into a program by placing | |
129 | arbitrary code in the <span class="file">.pythonrc.py</span> file. | |
130 | ||
131 | <P> | |
132 | Modules for general use should <em>not</em> import this module; it may | |
133 | interfere with the operation of the importing program. | |
134 | ||
135 | <P> | |
136 | <div class="seealso"> | |
137 | <p class="heading">See Also:</p> | |
138 | ||
139 | <dl compact="compact" class="seemodule"> | |
140 | <dt>Module <b><tt class="module"><a href="module-site.html">site</a></tt>:</b> | |
141 | <dd>Site-wide customization mechanism. | |
142 | </dl> | |
143 | </div> | |
144 | ||
145 | <DIV CLASS="navigation"> | |
146 | <div class='online-navigation'> | |
147 | <p></p><hr /> | |
148 | <table align="center" width="100%" cellpadding="0" cellspacing="2"> | |
149 | <tr> | |
150 | <td class='online-navigation'><a rel="prev" title="3.30 site " | |
151 | href="module-site.html"><img src='../icons/previous.png' | |
152 | border='0' height='32' alt='Previous Page' width='32' /></A></td> | |
153 | <td class='online-navigation'><a rel="parent" title="3. Python Runtime Services" | |
154 | href="python.html"><img src='../icons/up.png' | |
155 | border='0' height='32' alt='Up One Level' width='32' /></A></td> | |
156 | <td class='online-navigation'><a rel="next" title="3.32 __builtin__ " | |
157 | href="module-builtin.html"><img src='../icons/next.png' | |
158 | border='0' height='32' alt='Next Page' width='32' /></A></td> | |
159 | <td align="center" width="100%">Python Library Reference</td> | |
160 | <td class='online-navigation'><a rel="contents" title="Table of Contents" | |
161 | href="contents.html"><img src='../icons/contents.png' | |
162 | border='0' height='32' alt='Contents' width='32' /></A></td> | |
163 | <td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png' | |
164 | border='0' height='32' alt='Module Index' width='32' /></a></td> | |
165 | <td class='online-navigation'><a rel="index" title="Index" | |
166 | href="genindex.html"><img src='../icons/index.png' | |
167 | border='0' height='32' alt='Index' width='32' /></A></td> | |
168 | </tr></table> | |
169 | <div class='online-navigation'> | |
170 | <b class="navlabel">Previous:</b> | |
171 | <a class="sectref" rel="prev" href="module-site.html">3.30 site </A> | |
172 | <b class="navlabel">Up:</b> | |
173 | <a class="sectref" rel="parent" href="python.html">3. Python Runtime Services</A> | |
174 | <b class="navlabel">Next:</b> | |
175 | <a class="sectref" rel="next" href="module-builtin.html">3.32 __builtin__ </A> | |
176 | </div> | |
177 | </div> | |
178 | <hr /> | |
179 | <span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span> | |
180 | </DIV> | |
181 | <!--End of Navigation Panel--> | |
182 | <ADDRESS> | |
183 | See <i><a href="about.html">About this document...</a></i> for information on suggesting changes. | |
184 | </ADDRESS> | |
185 | </BODY> | |
186 | </HTML> |