trAvis - MANAGER
Edit File: ListOptions.html
<!-- $Id: ListOptions.html,v 1.6 2012-02-02 00:40:13 castaglia Exp $ --> <!-- $Source: /home/proftpd-core/backup/proftp-cvsroot/proftpd/doc/howto/ListOptions.html,v $ --> <html> <head> <title>ProFTPD mini-HOWTO - Directory Lists and ListOptions</title> </head> <body bgcolor=white> <hr> <center><h2><b>Directory Lists and <code>ListOptions</code></b></h2></center> <hr> <p> The <code><a href="http://www.proftpd.org/docs/directives/linked/config_ref_ListOptions.html">ListOptions</a></code> directive of ProFTPD can be used to control how directory listings are generated. Directory listings are sent in response to the <code>LIST</code> and <code>NLST</code> FTP commands. <p> The <code>ListOptions</code> directive supports the following options: <ul> <li><dt>-1</dt> <dd>List one file per line</dd> <li><dt>-A</dt> <dd>List all files except "." and ".."</dd> <li><dt>-a</dt> <dd>List all files including those whose names start with "."</dd> <li><dt>-B</dt> <dd>Force printing of non-printable filename characters as \<i>xxx</i>, where <i>xxx</i> is the octal value of the character</dd> <li><dt>-C</dt> <dd>List entries by columns</dd> <li><dt>-c<dt> <dd>Sort by file status change time when <code>-t</code> is also used</dd> <li><dt>-d</dt> <dd>List directory entries instead of directory contents</dd> <li><dt>-F</dt> <dd>Append file type indicator (one of "*", "/", "=", "@" or "|") to names</dd> <li><dt>-h</dt> <dd>Print file sizes in human-readable format (<i>e.g.</i> 1K, 234M, 2G)</dd> <li><dt>-L</dt> <dd>List files pointed to by symlinks</dd> <li><dt>-l</dt> <dd>Use a long listing format</dd> <li><dt>-n</dt> <dd>List numeric UIDs/GIDs instead of user/group names</dd> <li><dt>-R</dt> <dd>List subdirectories recursively</dd> <li><dt>-r</dt> <dd>Sort filenames in reverse order</dd> <li><dt>-S</dt> <dd>Sort by file size</dd> <li><dt>-t</dt> <dd>Sort by file modification time</dd> <li><dt>-u<dt> <dd>Sort by file access time when <code>-t</code> is also used</dd> </ul> <p> Although not strictly supported by the FTP RFCs, many FTP clients send these options with the <code>LIST</code> and <code>NLST</code> commands, and many FTP servers honor them. The <code>ListOptions</code> directive configures default options to be used, in addition to any sent by the client. For example, to show all files except the "hidden" files for clients, you could use: <pre> ListOptions -a </pre> <p> Another use of <code>ListOptions</code> is to <i>prevent</i> certain options from being used. The <code>-R</code> option, for recursively listing all subdirectories, can use a lot of system resources, especially on very large and/or very deep directory structures, as <code>proftpd</code> scans all of the files. For this reason, some sites may wish to prevent the <code>-R</code> option from being used. <code>ListOptions</code> supports this with use of the "+" character. Options are enabled using the "-" character, thus they are disabled using "+"--think of the "+" as cancelling out the "-". For example: <pre> ListOptions +R strict </pre> would disable all use of the <code>-R</code> option. <p> Where did the <code>strict</code> come from in the example above? <code>ListOptions</code> configures a set of default options, but if a client sends its own directory options, <code>proftpd</code> will use the client's options instead. To ignore the client options and use <i>only</i> the <code>ListOptions</code> configured, one uses the "strict" keyword. That is why the <code>+R</code> example above required "strict"--it causes <code>proftpd</code> to ignore any <code>-R</code> option the client might send. <p> What if you wanted to enable some options and disable others in the same <code>ListOptions</code> directive? You would surround your options in quotation marks, like so: <pre> ListOptions "-a +R" strict </pre> <p> If you are <b>not</b> using the <code>--enable-nls</code> configure option, <i>and</i> you want to see non-printable characters in filenames when listing directories, you should use: <pre> ListOptions -B </pre> <p> The following keywords are supported, in addition to "strict": <ul> <li><dt>maxfiles</dt> <dd>Sets a maximum limit on the number of files listed in one directory listing</dd> <li><dt>maxdirs</dt> <dd>Sets a maximum limit on the number of directories listed in one directory listing</dd> <li><dt>maxdepth</dt> <dd>Sets a maximum recursion depth, if the <code>-R</code> option is allowed</dd> <li><dt>LISTOnly</dt> <dd>Applies the <code>ListOptions</code> only to <code>LIST</code> commands (and not <code>NLST</code> or <code>STAT</code> commands) <li><dt>NLSTOnly</dt> <dd>Applies the <code>ListOptions</code> only to <code>NLST</code> commands (and not <code>LIST</code> or <code>STAT</code> commands) <li><dt>NoErrorIfAbsent</dt> <dd>Causes a 226 response code to be returned for <code>LIST/NLST</code> commands for files which do not exist, rather than 450 </ul> These keywords were added for finer-grained control over directory listings. They make it possible to allow recursive listings and yet still apply limits, to keep the recursion from taking too long: <pre> ListOptions -a maxfiles 2000 maxdepth 3 </pre> This configures the <code>-a</code> option by default, and limits the maximum files in the generated listing to 2000. If the client uses the <code>-R</code> option, <code>proftpd</code> will not recurse into directories more than 3 levels deep when generating the listing. <p> Or perhaps you want the one-file-per-line format, but only for <code>NLST</code> commands and <b>not</b> <code>LIST</code> commands. You would thus use something like: <pre> ListOptions "-1" strict NLSTOnly </pre> <p> Note that <code><a href="Limit.html"><Limit></a></code> sections can be used to block the <code>LIST</code> and <code>NLST</code> commands altogether. <p> <hr> <i>$Date: 2012-02-02 00:40:13 $</i><br> </body> </html>