glib-miscellaneous-utility-functions.html

glid编写实例

<h3 class="title">Warning</h3>
<p><code class="literal">g_dirname</code> is deprecated and should not be used in newly-written code.</p>
</div>
<p>
This function is deprecated and will be removed in the next major
release of GLib. Use <a href="glib-Miscellaneous-Utility-Functions.html#g-path-get-dirname"><code class="function">g_path_get_dirname()</code></a> instead.
</p>
<p>
Gets the directory components of a file name.
If the file name has no directory components "." is returned.
The returned string should be freed when no longer needed.
</p>
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<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td>the directory components of the file.


</td>
</tr></tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022282"></a><h3>
<a name="g-path-is-absolute"></a>g_path_is_absolute ()</h3>
<a class="indexterm" name="id3022293"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gboolean">gboolean</a>    g_path_is_absolute              (const <a href="glib-Basic-Types.html#gchar">gchar</a> *file_name);</pre>
<p>
Returns <code class="literal">TRUE</code> if the given <em class="parameter"><code>file_name</code></em> is an absolute file name,
i.e. it contains a full path from the root directory such as '/usr/local'
on UNIX or 'C:\windows' on Windows systems.
</p>
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<td>
<span class="term"><em class="parameter"><code>file_name</code></em>&#160;:</span></td>
<td>a file name.
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td>
<code class="literal">TRUE</code> if <em class="parameter"><code>file_name</code></em> is an absolute path.


</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022375"></a><h3>
<a name="g-path-skip-root"></a>g_path_skip_root ()</h3>
<a class="indexterm" name="id3022385"></a><pre class="programlisting">const <a href="glib-Basic-Types.html#gchar">gchar</a>* g_path_skip_root               (const <a href="glib-Basic-Types.html#gchar">gchar</a> *file_name);</pre>
<p>
Returns a pointer into <em class="parameter"><code>file_name</code></em> after the root component, i.e. after
the '/' in UNIX or 'C:\' under Windows. If <em class="parameter"><code>file_name</code></em> is not an absolute
path it returns <code class="literal">NULL</code>.
</p>
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<td>
<span class="term"><em class="parameter"><code>file_name</code></em>&#160;:</span></td>
<td>a file name.
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td>a pointer into <em class="parameter"><code>file_name</code></em> after the root component.


</td>
</tr>
</tbody>
</table></div>
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<hr>
<div class="refsect2" lang="en">
<a name="id3022470"></a><h3>
<a name="g-path-get-basename"></a>g_path_get_basename ()</h3>
<a class="indexterm" name="id3022481"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gchar">gchar</a>*      g_path_get_basename             (const <a href="glib-Basic-Types.html#gchar">gchar</a> *file_name);</pre>
<p>
Gets the last component of the filename. If <em class="parameter"><code>file_name</code></em> ends with a 
directory separator it gets the component before the last slash. If 
<em class="parameter"><code>file_name</code></em> consists only of directory separators (and on Windows, 
possibly a drive letter), a single separator is returned. If
<em class="parameter"><code>file_name</code></em> is empty, it gets ".".</p>
<p>

</p>
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<td>
<span class="term"><em class="parameter"><code>file_name</code></em>&#160;:</span></td>
<td> the name of the file.
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td> a newly allocated string containing the last component of 
  the filename.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022564"></a><h3>
<a name="g-path-get-dirname"></a>g_path_get_dirname ()</h3>
<a class="indexterm" name="id3022576"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gchar">gchar</a>*      g_path_get_dirname              (const <a href="glib-Basic-Types.html#gchar">gchar</a> *file_name);</pre>
<p>
Gets the directory components of a file name.  If the file name has no
directory components "." is returned.  The returned string should be
freed when no longer needed.
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
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<td>
<span class="term"><em class="parameter"><code>file_name</code></em>&#160;:</span></td>
<td>the name of the file.
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td>the directory components of the file.


</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022636"></a><h3>
<a name="g-build-filename"></a>g_build_filename ()</h3>
<a class="indexterm" name="id3022646"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gchar">gchar</a>*      g_build_filename                (const <a href="glib-Basic-Types.html#gchar">gchar</a> *first_element,
                                             ...);</pre>
<p>
Creates a filename from a series of elements using the correct
separator for filenames.
</p>
<p>
On Unix, this function behaves identically to <code class="literal">g_build_path
(G_DIR_SEPARATOR_S, first_element, ....)</code>.
</p>
<p>
On Windows, it takes into account that either the backslash
(<code class="literal">\</code> or slash (<code class="literal">/</code>) can be used
as separator in filenames, but otherwise behaves as on Unix. When
file pathname separators need to be inserted, the one that last
previously occurred in the parameters (reading from left to right)
is used.
</p>
<p>
No attempt is made to force the resulting filename to be an absolute
path. If the first element is a relative path, the result will
be a relative path.</p>
<p>

</p>
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<td>
<span class="term"><em class="parameter"><code>first_element</code></em>&#160;:</span></td>
<td> the first element in the path
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>...</code></em>&#160;:</span></td>
<td> remaining elements in path, terminated by <code class="literal">NULL</code>
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td> a newly-allocated string that must be freed with <a href="glib-Memory-Allocation.html#g-free"><code class="function">g_free()</code></a>.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022776"></a><h3>
<a name="g-build-path"></a>g_build_path ()</h3>
<a class="indexterm" name="id3022786"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gchar">gchar</a>*      g_build_path                    (const <a href="glib-Basic-Types.html#gchar">gchar</a> *separator,
                                             const <a href="glib-Basic-Types.html#gchar">gchar</a> *first_element,
                                             ...);</pre>
<p>
Creates a path from a series of elements using <em class="parameter"><code>separator</code></em> as the
separator between elements. At the boundary between two elements,
any trailing occurrences of separator in the first element, or
leading occurrences of separator in the second element are removed
and exactly one copy of the separator is inserted.
</p>
<p>
Empty elements are ignored.
</p>
<p>
The number of leading copies of the separator on the result is
the same as the number of leading copies of the separator on
the first non-empty element.
</p>
<p>
The number of trailing copies of the separator on the result is
the same as the number of trailing copies of the separator on
the last non-empty element. (Determination of the number of
trailing copies is done without stripping leading copies, so
if the separator is <code class="literal">ABA</code>, <code class="literal">ABABA</code>
has 1 trailing copy.)
</p>
<p>
However, if there is only a single non-empty element, and there
are no characters in that element not part of the leading or
trailing separators, then the result is exactly the original value
of that element.
</p>
<p>
Other than for determination of the number of leading and trailing
copies of the separator, elements consisting only of copies
of the separator are ignored.</p>
<p>

</p>
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<span class="term"><em class="parameter"><code>separator</code></em>&#160;:</span></td>
<td> a string used to separator the elements of the path.
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>first_element</code></em>&#160;:</span></td>
<td> the first element in the path
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>...</code></em>&#160;:</span></td>
<td> remaining elements in path, terminated by <code class="literal">NULL</code>
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td> a newly-allocated string that must be freed with <a href="glib-Memory-Allocation.html#g-free"><code class="function">g_free()</code></a>.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3022954"></a><h3>
<a name="g-find-program-in-path"></a>g_find_program_in_path ()</h3>
<a class="indexterm" name="id3022965"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gchar">gchar</a>*      g_find_program_in_path          (const <a href="glib-Basic-Types.html#gchar">gchar</a> *program);</pre>
<p>
Locates the first executable named <em class="parameter"><code>program</code></em> in the user's path, in the
same way that <code class="function">execvp()</code> would locate it. Returns an allocated string
with the absolute path name, or <code class="literal">NULL</code> if the program is not found in
the path. If <em class="parameter"><code>program</code></em> is already an absolute path, returns a copy of
<em class="parameter"><code>program</code></em> if <em class="parameter"><code>program</code></em> exists and is executable, and <code class="literal">NULL</code> otherwise.
 
On Windows, if <em class="parameter"><code>program</code></em> does not have a file type suffix, tries
with the suffixes .exe, .cmd, .bat and .com, and the suffixes in
the <code class="envar">PATHEXT</code> environment variable.
</p>
<p>
It looks for the file in the same way as <code class="function">CreateProcess()</code>
would. This means first in the directory where the executing
program was loaded from, then in the current directory, then in the
Windows 32-bit system directory, then in the Windows directory, and
finally in the directories in the <code class="envar">PATH</code> environment 
variable. If the program is found, the return value contains the 
full name including the type suffix.</p>
<p>

</p>
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<span class="term"><em class="parameter"><code>program</code></em>&#160;:</span></td>
<td> a program name in the GLib file name encoding
</td>
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<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></td>
<td> absolute path, or <code class="literal">NULL</code>
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3023121"></a><h3>
<a name="g-bit-nth-lsf"></a>g_bit_nth_lsf ()</h3>
<a class="indexterm" name="id3023131"></a><pre class="programlisting"><a href="glib-Basic-Types.html#gint">gint</a>        g_bit_nth_lsf                   (<a href="glib-Basic-Types.html#gulong">gulong</a> mask,
                                             <a href="glib-Basic-Types.html#gint">gint</a> nth_bit);</pre>