ref: 885d41dd7b87c41cb618140d50dd23501b6d4279
dir: /sys/man/4/ftpfs/
.TH FTPFS 4 .SH NAME ftpfs \- file transfer protocol (FTP) file system .SH SYNOPSIS .B ftpfs [ .B -/dqnt ] [ .B -m .I mountpoint ] [ .B -a .I password ] [ .B -e .I ext ] [ .B -k .I keyspec ] [ .B -o .I os ] [ .B -r remoteroot ] .I system .SH DESCRIPTION .I Ftpfs dials the TCP file transfer protocol (FTP) port, 21, on .I system and mounts itself (see .IR bind (2)) on .I mountpoint (default .BR /n/ftp ) to provide access via FTP to files on the remote machine. .I Ftpfs attempts to use FTP's `passive' mode but falls back to using `active' mode if that fails. If required by the remote machine, .I ftpfs will ask .IR factotum (4) for a key matching the pattern .IP .EX proto=pass service=ftp server=\fIsystem\fP user? !password? \fIkeyspec\fP .EE .PP (If .I factotum does not have such a key, .I factotum will prompt the user for one.) .PP The user names .B ftp and .B anonymous conventionally offer guest/read-only access to machines. Anonymous FTP may be called without using factotum by using the .B -a option and specifying the .IR password . .PP By default the file seen at the mount point is the user's remote home directory if he has one. The option .B -/ forces the mount point to correspond to the remote root. The option .B -r forces the mount point to correspond to the remote directory .IR remoteroot . .PP To avoid seeing startup messages from the server use option .BR -q . To see all messages from the server use option .BR -d . .PP Some systems will hangup an ftp connection that has no activity for a given period. The .BR -K option causes ftp to send a NOP command every 15 seconds to attempt to keep the connection open. This command can cause some servers to hangup, so you'll have to feel your way. .PP The .B -t option causes .I ftpfs to negotiate TLS encryption with the server. .PP To terminate the connection, .B unmount (see .IR bind (1)) the mount point. .PP Since there is no specified format for metadata retrieved in response to an FTP directory request, .I ftpfs has to apply heuristics to steer the interpretation. Sometimes, though rarely, these heuristics fail. The following options are meant as last resorts to try to steer interpretation. .PP A major clue to the heuristics is the operating system at the other end. Normally this can be determined automatically using the FTP SYST command. However, in some cases the server doesn't implement the SYST command. The .B -o option will force the case by specifying the name of the operating system. Known system types are: .BR UNIX , .BR SUN , .BR TOPS , .BR Plan9 , .BR VM , .BR VMS , .BR MVS , .BR NetWare , .BR OS/2 , .BR TSO , and .BR WINDOWS_NT . .PP Some systems and/or FTP servers return directory listings that don't include the file extension. The .B -e option allows the user to specify an extension to append to all remote files (other than directories). .PP Finally, there are two FTP commands to retrieve the contents of a directory, LIST and NLST. LIST is approximately equivalent to .L ls -l and NLST to .LR ls . .I Ftpfs normally uses LIST. However, some FTP servers interpret LIST to mean, give a wordy description of the file. .I Ftpfs normally notices this and switches to using NLST. However, in some rare cases, the user must force the use of NLST with the .B -n option. .SH EXAMPLE You want anonymous FTP access to the system .BR export.lcs.mit.edu . The first .IR import (4) command is only necessary if your machine does not have access to the desired system, but another, called .B gateway in this example, does. .IP .EX import gateway /net ftpfs -a yourname@yourmachine export.lcs.mit.edu .EE .SH SOURCE .B /sys/src/cmd/ip/ftpfs .SH "SEE ALSO" .IR bind (2) .SH BUGS Symbolic links on remote Unix systems will always have mode 0777 and a length of 8. .PP After connecting to a TOPS-20 system, the mount point will contain only one directory, usually .BR /n/ftp/PS:<ANONYMOUS> . However, walking to any valid directory on that machine will succeed and cause that directory entry to appear under the mount point. .PP .I Ftpfs caches files and directories. A directory will fall from the cache after 5 quiescent minutes or if the local user changes the directory by writing or removing a file. Otherwise, remote changes to the directory that occur after the directory has been cached might not be immediately visible. Attempting to walk to .IB directory /.flush.ftpfs will flush .I directory from the cache, thus forcing .I ftpfs to re-read it. .PP There is no way to issue the appropriate commands to handle special synthetic FTP file types such as directories that automatically return a .B tar of their contents. .PP .I Ftpfs makes copies in .B /tmp of files being transferred, so its effects might not be immediate. If there is enough main memory, you might want to run .IR ramfs (4) first. .PP Filenames containing spaces will confuse .I ftpfs (and other FTP clients).