Viewing file:  ListOptions.html (6.18 KB) -rw-r--r--
Select action/file-type:
 (+) | (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
ProFTPD: Directory Lists and ListOptions
Directory Lists and ListOptions
The ListOptions
directive of ProFTPD can be used to control how directory listings are
generated. Directory listings are sent in response to the LIST
and NLST FTP commands.
The ListOptions directive supports the following options:
- -1
- List one file per line
- -A
- List all files except "." and ".."
- -a
- List all files including those whose names start with "."
- -B
- Force printing of non-printable filename characters as \xxx, where xxx is the octal value of the character
- -C
- List entries by columns
- -c
-
- Sort by file status change time when
-t is also used
- -d
- List directory entries instead of directory contents
- -F
- Append file type indicator (one of "*", "/", "=", "@" or "|") to names
- -h
- Print file sizes in human-readable format (e.g. 1K, 234M, 2G)
- -L
- List files pointed to by symlinks
- -l
- Use a long listing format
- -n
- List numeric UIDs/GIDs instead of user/group names
- -R
- List subdirectories recursively
- -r
- Sort filenames in reverse order
- -S
- Sort by file size
- -t
- Sort by file modification time
- -U
-
- Do not sort; list entries in directory order
- -u
-
- Sort by file access time when
-t is also used
Although not strictly supported by the FTP RFCs, many FTP clients send these
options with the LIST and NLST commands, and many
FTP servers honor them. The ListOptions 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:
ListOptions -a
Another use of ListOptions is to prevent certain options
from being used. The -R option, for recursively listing
all subdirectories, can use a lot of system resources, especially on very
large and/or very deep directory structures, as proftpd scans
all of the files. For this reason, some sites may wish to prevent the
-R option from being used. ListOptions 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:
ListOptions +R strict
would disable all use of the -R option.
Where did the strict come from in the example above?
ListOptions configures a set of default options, but if a client
sends its own directory options, proftpd will use the client's
options instead. To ignore the client options and use only the
ListOptions configured, one uses the "strict" keyword.
That is why the +R example above required
"strict"--it causes proftpd to ignore any
-R option the client might send.
What if you wanted to enable some options and disable others in the same
ListOptions directive? You would surround your options in quotation marks, like so:
ListOptions "-a +R" strict
If you are not using the --enable-nls configure option,
and you want to see non-printable characters in filenames when listing
directories, you should use:
ListOptions -B
The following keywords are supported, in addition to "strict":
- maxfiles
- Sets a maximum limit on the number of files listed in one directory listing
- maxdirs
- Sets a maximum limit on the number of directories listed in one directory listing
- maxdepth
- Sets a maximum recursion depth, if the
-R option is allowed
- LISTOnly
- Applies the
ListOptions only to LIST commands (and not NLST or STAT commands)
- NLSTOnly
- Applies the
ListOptions only to NLST commands (and not LIST or STAT commands)
- NoErrorIfAbsent
- Causes a 226 response code to be returned for
LIST/NLST commands for files which do not exist, rather than 450
- SortedNLST
- Causes the
NLST results to be sorted by name
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:
ListOptions -a maxfiles 2000 maxdepth 3
This configures the -a option by default, and limits the maximum
files in the generated listing to 2000. If the client uses the -R
option, proftpd will not recurse into directories more than 3
levels deep when generating the listing.
Or perhaps you want the one-file-per-line format, but only for
NLST commands and not LIST commands. You
would thus use something like:
ListOptions "-1" strict NLSTOnly
Note that <Limit> sections can be
used to block the LIST and NLST commands altogether.
© Copyright 2017 The ProFTPD Project
All Rights Reserved
|