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The entry should look like: </p> <div class="literalblock"> <div class="content"> <pre><tt>{ "foo", cmd_foo, <options> },</tt></pre> </div></div> <div class="paragraph"><p>where options is the bitwise-or of:</p></div> <div class="dlist"><dl> <dt class="hdlist1"> <tt>RUN_SETUP</tt> </dt> <dd> <p> Make sure there is a git directory to work on, and if there is a work tree, chdir to the top of it if the command was invoked in a subdirectory. If there is no work tree, no chdir() is done. </p> </dd> <dt class="hdlist1"> <tt>USE_PAGER</tt> </dt> <dd> <p> If the standard output is connected to a tty, spawn a pager and feed our output to it. </p> </dd> <dt class="hdlist1"> <tt>NEED_WORK_TREE</tt> </dt> <dd> <p> Make sure there is a work tree, i.e. the command cannot act on bare repositories. This only makes sense when <tt>RUN_SETUP</tt> is also set. </p> </dd> </dl></div> </li> <li> <p> Add <tt>builtin-foo.o</tt> to <tt>BUILTIN_OBJS</tt> in <tt>Makefile</tt>. </p> </li> </ol></div> <div class="paragraph"><p>Additionally, if <tt>foo</tt> is a new command, there are 3 more things to do:</p></div> <div class="olist arabic"><ol class="arabic"> <li> <p> Add tests to <tt>t/</tt> directory. </p> </li> <li> <p> Write documentation in <tt>Documentation/git-foo.txt</tt>. </p> </li> <li> <p> Add an entry for <tt>git-foo</tt> to <tt>command-list.txt</tt>. </p> </li> </ol></div> </div> <h2 id="_how_a_built_in_is_called">How a built-in is called</h2> <div class="sectionbody"> <div class="paragraph"><p>The implementation <tt>cmd_foo()</tt> takes three parameters, <tt>argc</tt>, <tt>argv, and `prefix</tt>. The first two are similar to what <tt>main()</tt> of a standalone command would be called with.</p></div> <div class="paragraph"><p>When <tt>RUN_SETUP</tt> is specified in the <tt>commands[]</tt> table, and when you were started from a subdirectory of the work tree, <tt>cmd_foo()</tt> is called after chdir(2) to the top of the work tree, and <tt>prefix</tt> gets the path to the subdirectory the command started from. This allows you to convert a user-supplied pathname (typically relative to that directory) to a pathname relative to the top of the work tree.</p></div> <div class="paragraph"><p>The return value from <tt>cmd_foo()</tt> becomes the exit status of the command.</p></div> </div> <div id="footer"> <div id="footer-text"> Last updated 2009-04-28 08:54:57 UTC </div> </div> </body> </html>