ZSHZFTPSYS(1) User Commands ZSHZFTPSYS(1)

NAME

zshzftpsys - zftp function front-end

DESCRIPTION

This describes the set of shell functions supplied with the source
distribution as an interface to the zftp builtin command, allowing
you to perform FTP operations from the shell command line or within
functions or scripts. The interface is similar to a traditional FTP
client (e.g. the ftp command itself, see ftp(1)), but as it is
entirely done within the shell all the familiar completion, editing
and globbing features, and so on, are present, and macros are
particularly simple to write as they are just ordinary shell
functions.

The prerequisite is that the zftp command, as described in
zshmodules(1) , must be available in the version of zsh installed at
your site. If the shell is configured to load new commands at run
time, it probably is: typing `zmodload zsh/zftp' will make sure (if
that runs silently, it has worked). If this is not the case, it is
possible zftp was linked into the shell anyway: to test this, type
`which zftp' and if zftp is available you will get the message `zftp:
shell built-in command'.

Commands given directly with zftp builtin may be interspersed between
the functions in this suite; in a few cases, using zftp directly may
cause some of the status information stored in shell parameters to
become invalid. Note in particular the description of the variables
$ZFTP_TMOUT, $ZFTP_PREFS and $ZFTP_VERBOSE for zftp.

INSTALLATION

You should make sure all the functions from the Functions/Zftp
directory of the source distribution are available; they all begin
with the two letters `zf'. They may already have been installed on
your system; otherwise, you will need to find them and copy them.
The directory should appear as one of the elements of the $fpath
array (this should already be the case if they were installed), and
at least the function zfinit should be autoloaded; it will autoload
the rest. Finally, to initialize the use of the system you need to
call the zfinit function. The following code in your .zshrc will
arrange for this; assume the functions are stored in the directory
~/myfns:

fpath=(~/myfns $fpath)
autoload -U zfinit
zfinit

Note that zfinit assumes you are using the zmodload method to load
the zftp command. If it is already built into the shell, change
zfinit to zfinit -n. It is helpful (though not essential) if the
call to zfinit appears after any code to initialize the new
completion system, else unnecessary compctl commands will be given.

FUNCTIONS

The sequence of operations in performing a file transfer is
essentially the same as that in a standard FTP client. Note that,
due to a quirk of the shell's getopts builtin, for those functions
that handle options you must use `--' rather than `-' to ensure the
remaining arguments are treated literally (a single `-' is treated as
an argument).

Opening a connection

zfparams [ host [ user [ password ... ] ] ]
Set or show the parameters for a future zfopen with no
arguments. If no arguments are given, the current parameters
are displayed (the password will be shown as a line of
asterisks). If a host is given, and either the user or
password is not, they will be prompted for; also, any
parameter given as `?' will be prompted for, and if the `?' is
followed by a string, that will be used as the prompt. As
zfopen calls zfparams to store the parameters, this usually
need not be called directly.

A single argument `-' will delete the stored parameters. This
will also cause the memory of the last directory (and so on)
on the other host to be deleted.

zfopen [ -1 ] [ host [ user [ password [ account ] ] ] ]
If host is present, open a connection to that host under
username user with password password (and, on the rare
occasions when it is necessary, account account). If a
necessary parameter is missing or given as `?' it will be
prompted for. If host is not present, use a previously stored
set of parameters.

If the command was successful, and the terminal is compatible
with xterm or is sun-cmd, a summary will appear in the title
bar, giving the local host:directory and the remote
host:directory; this is handled by the function zftp_chpwd,
described below.

Normally, the host, user and password are internally recorded
for later re-opening, either by a zfopen with no arguments, or
automatically (see below). With the option `-1', no
information is stored. Also, if an open command with
arguments failed, the parameters will not be retained (and any
previous parameters will also be deleted). A zfopen on its
own, or a zfopen -1, never alters the stored parameters.

Both zfopen and zfanon (but not zfparams) understand URLs of
the form ftp://host/path... as meaning to connect to the host,
then change directory to path (which must be a directory, not
a file). The `ftp://' can be omitted; the trailing `/' is
enough to trigger recognition of the path. Note prefixes
other than `ftp:' are not recognized, and that all characters
after the first slash beyond host are significant in path.

zfanon [ -1 ] host
Open a connection host for anonymous FTP. The username used
is `anonymous'. The password (which will be reported the
first time) is generated as user@host; this is then stored in
the shell parameter $EMAIL_ADDR which can alternatively be set
manually to a suitable string.

Directory management

zfcd [ dir ]
zfcd -
zfcd old new
Change the current directory on the remote server: this is
implemented to have many of the features of the shell builtin
cd.

In the first form with dir present, change to the directory
dir. The command `zfcd ..' is treated specially, so is
guaranteed to work on non-UNIX servers (note this is handled
internally by zftp). If dir is omitted, has the effect of
`zfcd ~'.

The second form changes to the directory previously current.

The third form attempts to change the current directory by
replacing the first occurrence of the string old with the
string new in the current directory.

Note that in this command, and indeed anywhere a remote
filename is expected, the string which on the local host
corresponds to `~' is converted back to a `~' before being
passed to the remote machine. This is convenient because of
the way expansion is performed on the command line before zfcd
receives a string. For example, suppose the command is `zfcd
~/foo'. The shell will expand this to a full path such as
`zfcd /home/user2/pws/foo'. At this stage, zfcd recognises
the initial path as corresponding to `~' and will send the
directory to the remote host as ~/foo, so that the `~' will be
expanded by the server to the correct remote host directory.
Other named directories of the form `~name' are not treated in
this fashion.

zfhere Change directory on the remote server to the one corresponding
to the current local directory, with special handling of `~'
as in zfcd. For example, if the current local directory is
~/foo/bar, then zfhere performs the effect of `zfcd
~/foo/bar'.

zfdir [ -rfd ] [ - ] [ dir-options ] [ dir ]
Produce a long directory listing. The arguments dir-options
and dir are passed directly to the server and their effect is
implementation dependent, but specifying a particular remote
directory dir is usually possible. The output is passed
through a pager given by the environment variable $PAGER, or
`more' if that is not set.

The directory is usually cached for re-use. In fact, two
caches are maintained. One is for use when there is no
dir-options or dir, i.e. a full listing of the current remote
directory; it is flushed when the current remote directory
changes. The other is kept for repeated use of zfdir with the
same arguments; for example, repeated use of `zfdir /pub/gnu'
will only require the directory to be retrieved on the first
call. Alternatively, this cache can be re-viewed with the -r
option. As relative directories will confuse zfdir, the -f
option can be used to force the cache to be flushed before the
directory is listed. The option -d will delete both caches
without showing a directory listing; it will also delete the
cache of file names in the current remote directory, if any.

zfls [ ls-options ] [ dir ]
List files on the remote server. With no arguments, this will
produce a simple list of file names for the current remote
directory. Any arguments are passed directly to the server.
No pager and no caching is used.

Status commands

zftype [ type ]
With no arguments, show the type of data to be transferred,
usually ASCII or binary. With an argument, change the type:
the types `A' or `ASCII' for ASCII data and `B' or `BINARY',
`I' or `IMAGE' for binary data are understood
case-insensitively.

zfstat [ -v ]
Show the status of the current or last connection, as well as
the status of some of zftp's status variables. With the -v
option, a more verbose listing is produced by querying the
server for its version of events, too.

Retrieving files

The commands for retrieving files all take at least two options. -G
suppresses remote filename expansion which would otherwise be
performed (see below for a more detailed description of that). -t
attempts to set the modification time of the local file to that of
the remote file: see the description of the function zfrtime below
for more information.

zfget [ -Gtc ] file1 ...
Retrieve all the listed files file1 ... one at a time from the
remote server. If a file contains a `/', the full name is
passed to the remote server, but the file is stored locally
under the name given by the part after the final `/'. The
option -c (cat) forces all files to be sent as a single stream
to standard output; in this case the -t option has no effect.

zfuget [ -Gvst ] file1 ...
As zfget, but only retrieve files where the version on the
remote server is newer (has a later modification time), or
where the local file does not exist. If the remote file is
older but the files have different sizes, or if the sizes are
the same but the remote file is newer, the user will usually
be queried. With the option -s, the command runs silently and
will always retrieve the file in either of those two cases.
With the option -v, the command prints more information about
the files while it is working out whether or not to transfer
them.

zfcget [ -Gt ] file1 ...
As zfget, but if any of the local files exists, and is shorter
than the corresponding remote file, the command assumes that
it is the result of a partially completed transfer and
attempts to transfer the rest of the file. This is useful on
a poor connection which keeps failing.

Note that this requires a commonly implemented, but
non-standard, version of the FTP protocol, so is not
guaranteed to work on all servers.

zfgcp [ -Gt ] remote-file local-file
zfgcp [ -Gt ] rfile1 ... ldir
This retrieves files from the remote server with arguments
behaving similarly to the cp command.

In the first form, copy remote-file from the server to the
local file local-file.

In the second form, copy all the remote files rfile1 ... into
the local directory ldir retaining the same basenames. This
assumes UNIX directory semantics.

Sending files

zfput [ -r ] file1 ...
Send all the file1 ... given separately to the remote server.
If a filename contains a `/', the full filename is used
locally to find the file, but only the basename is used for
the remote file name.

With the option -r, if any of the files are directories they
are sent recursively with all their subdirectories, including
files beginning with `.'. This requires that the remote
machine understand UNIX file semantics, since `/' is used as a
directory separator.

zfuput [ -vs ] file1 ...
As zfput, but only send files which are newer than their
remote equivalents, or if the remote file does not exist. The
logic is the same as for zfuget, but reversed between local
and remote files.

zfcput file1 ...
As zfput, but if any remote file already exists and is shorter
than the local equivalent, assume it is the result of an
incomplete transfer and send the rest of the file to append to
the existing part. As the FTP append command is part of the
standard set, this is in principle more likely to work than
zfcget.

zfpcp local-file remote-file
zfpcp lfile1 ... rdir
This sends files to the remote server with arguments behaving
similarly to the cp command.

With two arguments, copy local-file to the server as
remote-file.

With more than two arguments, copy all the local files lfile1
... into the existing remote directory rdir retaining the same
basenames. This assumes UNIX directory semantics.

A problem arises if you attempt to use zfpcp lfile1 rdir, i.e.
the second form of copying but with two arguments, as the
command has no simple way of knowing if rdir corresponds to a
directory or a filename. It attempts to resolve this in
various ways. First, if the rdir argument is `.' or `..' or
ends in a slash, it is assumed to be a directory. Secondly,
if the operation of copying to a remote file in the first form
failed, and the remote server sends back the expected failure
code 553 and a reply including the string `Is a directory',
then zfpcp will retry using the second form.

Closing the connection

zfclose
Close the connection.

Session management

zfsession [ -lvod ] [ sessname ]
Allows you to manage multiple FTP sessions at once. By
default, connections take place in a session called `default';
by giving the command `zfsession sessname' you can change to a
new or existing session with a name of your choice. The new
session remembers its own connection, as well as associated
shell parameters, and also the host/user parameters set by
zfparams. Hence you can have different sessions set up to
connect to different hosts, each remembering the appropriate
host, user and password.

With no arguments, zfsession prints the name of the current
session; with the option -l it lists all sessions which
currently exist, and with the option -v it gives a verbose
list showing the host and directory for each session, where
the current session is marked with an asterisk. With -o, it
will switch to the most recent previous session.

With -d, the given session (or else the current one) is
removed; everything to do with it is completely forgotten. If
it was the only session, a new session called `default' is
created and made current. It is safest not to delete sessions
while background commands using zftp are active.

zftransfer sess1:file1 sess2:file2
Transfer files between two sessions; no local copy is made.
The file is read from the session sess1 as file1 and written
to session sess2 as file file2; file1 and file2 may be
relative to the current directories of the session. Either
sess1 or sess2 may be omitted (though the colon should be
retained if there is a possibility of a colon appearing in the
file name) and defaults to the current session; file2 may be
omitted or may end with a slash, in which case the basename of
file1 will be added. The sessions sess1 and sess2 must be
distinct.

The operation is performed using pipes, so it is required that
the connections still be valid in a subshell, which is not the
case under versions of some operating systems, presumably due
to a system bug.

Bookmarks

The two functions zfmark and zfgoto allow you to `bookmark' the
present location (host, user and directory) of the current FTP
connection for later use. The file to be used for storing and
retrieving bookmarks is given by the parameter $ZFTP_BMFILE; if not
set when one of the two functions is called, it will be set to the
file .zfbkmarks in the directory where your zsh startup files live
(usually ~).

zfmark [ bookmark ]
If given an argument, mark the current host, user and
directory under the name bookmark for later use by zfgoto. If
there is no connection open, use the values for the last
connection immediately before it was closed; it is an error if
there was none. Any existing bookmark under the same name
will be silently replaced.

If not given an argument, list the existing bookmarks and the
points to which they refer in the form user@host:directory;
this is the format in which they are stored, and the file may
be edited directly.

zfgoto [ -n ] bookmark
Return to the location given by bookmark, as previously set by
zfmark. If the location has user `ftp' or `anonymous', open
the connection with zfanon, so that no password is required.
If the user and host parameters match those stored for the
current session, if any, those will be used, and again no
password is required. Otherwise a password will be prompted
for.

With the option -n, the bookmark is taken to be a nickname
stored by the ncftp program in its bookmark file, which is
assumed to be ~/.ncftp/bookmarks. The function works
identically in other ways. Note that there is no mechanism
for adding or modifying ncftp bookmarks from the zftp
functions.

Other functions

Mostly, these functions will not be called directly (apart from
zfinit), but are described here for completeness. You may wish to
alter zftp_chpwd and zftp_progress, in particular.

zfinit [ -n ]
As described above, this is used to initialize the zftp
function system. The -n option should be used if the zftp
command is already built into the shell.

zfautocheck [ -dn ]
This function is called to implement automatic reopening
behaviour, as described in more detail below. The options
must appear in the first argument; -n prevents the command
from changing to the old directory, while -d prevents it from
setting the variable do_close, which it otherwise does as a
flag for automatically closing the connection after a
transfer. The host and directory for the last session are
stored in the variable $zflastsession, but the internal
host/user/password parameters must also be correctly set.

zfcd_match prefix suffix
This performs matching for completion of remote directory
names. If the remote server is UNIX, it will attempt to
persuade the server to list the remote directory with
subdirectories marked, which usually works but is not
guaranteed. On other hosts it simply calls zfget_match and
hence completes all files, not just directories. On some
systems, directories may not even look like filenames.

zfget_match prefix suffix
This performs matching for completion of remote filenames. It
caches files for the current directory (only) in the shell
parameter $zftp_fcache. It is in the form to be called by the
-K option of compctl, but also works when called from a
widget-style completion function with prefix and suffix set
appropriately.

zfrglob varname
Perform remote globbing, as describes in more detail below.
varname is the name of a variable containing the pattern to be
expanded; if there were any matches, the same variable will be
set to the expanded set of filenames on return.

zfrtime lfile rfile [ time ]
Set the local file lfile to have the same modification time as
the remote file rfile, or the explicit time time in FTP format
CCYYMMDDhhmmSS for the GMT timezone. This uses the shell's
zsh/datetime module to perform the conversion from GMT to
local time.

zftp_chpwd
This function is called every time a connection is opened, or
closed, or the remote directory changes. This version alters
the title bar of an xterm-compatible or sun-cmd terminal
emulator to reflect the local and remote hostnames and current
directories. It works best when combined with the function
chpwd. In particular, a function of the form

chpwd() {
if [[ -n $ZFTP_USER ]]; then
zftp_chpwd
else
# usual chpwd e.g put host:directory in title bar
fi
}

fits in well.

zftp_progress
This function shows the status of the transfer. It will not
write anything unless the output is going to a terminal;
however, if you transfer files in the background, you should
turn off progress reports by hand using `zstyle ':zftp:*'
progress none'. Note also that if you alter it, any output
must be to standard error, as standard output may be a file
being received. The form of the progress meter, or whether it
is used at all, can be configured without altering the
function, as described in the next section.

zffcache
This is used to implement caching of files in the current
directory for each session separately. It is used by
zfget_match and zfrglob.

MISCELLANEOUS FEATURES

Configuration

Various styles are available using the standard shell style
mechanism, described in zshmodules(1). Briefly, the command `zstyle
':zftp:*' style value ...'. defines the style to have value value;
more than one value may be given, although that is not useful in the
cases described here. These values will then be used throughout the
zftp function system. For more precise control, the first argument,
which gives a pattern that matches contexts in which the style
applies, can be modified to include a particular function, as for
example `:zftp:zfget': the style will then have the given value only
in the zfget function, and will override styles set under `:zftp:*'.
Note that only the top level function name, as called by the user, is
used; calling of lower level functions is transparent to the user.
Hence modifications to the title bar in zftp_chpwd use the contexts
:zftp:zfopen, :zftp:zfcd, etc., depending where it was called from.
The following styles are understood:

progress
Controls the way that zftp_progress reports on the progress of
a transfer. If empty, unset, or `none', no progress report is
made; if `bar' a growing bar of inverse video is shown; if
`percent' (or any other string, though this may change in
future), the percentage of the file transferred is shown. The
bar meter requires that the width of the terminal be available
via the $COLUMNS parameter (normally this is set
automatically). If the size of the file being transferred is
not available, bar and percent meters will simply show the
number of bytes transferred so far.

When zfinit is run, if this style is not defined for the
context :zftp:*, it will be set to `bar'.

update Specifies the minimum time interval between updates of the
progress meter in seconds. No update is made unless new data
has been received, so the actual time interval is limited only
by $ZFTP_TIMEOUT.

As described for progress, zfinit will force this to default
to 1.

remote-glob
If set to `1', `yes' or `true', filename generation (globbing)
is performed on the remote machine instead of by zsh itself;
see below.

titlebar
If set to `1', `yes' or `true', zftp_chpwd will put the remote
host and remote directory into the titlebar of terminal
emulators such as xterm or sun-cmd that allow this.

As described for progress, zfinit will force this to default
to 1.

chpwd If set to `1' `yes' or `true', zftp_chpwd will call the
function chpwd when a connection is closed. This is useful if
the remote host details were put into the terminal title bar
by zftp_chpwd and your usual chpwd also modifies the title
bar.

When zfinit is run, it will determine whether chpwd exists and
if so it will set the default value for the style to 1 if none
exists already.

Note that there is also an associative array zfconfig which contains
values used by the function system. This should not be modified or
overwritten.

Remote globbing

The commands for retrieving files usually perform filename generation
(globbing) on their arguments; this can be turned off by passing the
option -G to each of the commands. Normally this operates by
retrieving a complete list of files for the directory in question,
then matching these locally against the pattern supplied. This has
the advantage that the full range of zsh patterns (respecting the
setting of the option EXTENDED_GLOB) can be used. However, it means
that the directory part of a filename will not be expanded and must
be given exactly. If the remote server does not support the UNIX
directory semantics, directory handling is problematic and it is
recommended that globbing only be used within the current directory.
The list of files in the current directory, if retrieved, will be
cached, so that subsequent globs in the same directory without an
intervening zfcd are much faster.

If the remote-glob style (see above) is set, globbing is instead
performed on the remote host: the server is asked for a list of
matching files. This is highly dependent on how the server is
implemented, though typically UNIX servers will provide support for
basic glob patterns. This may in some cases be faster, as it avoids
retrieving the entire list of directory contents.

Automatic and temporary reopening

As described for the zfopen command, a subsequent zfopen with no
parameters will reopen the connection to the last host (this includes
connections made with the zfanon command). Opened in this fashion,
the connection starts in the default remote directory and will remain
open until explicitly closed.

Automatic re-opening is also available. If a connection is not
currently open and a command requiring a connection is given, the
last connection is implicitly reopened. In this case the directory
which was current when the connection was closed again becomes the
current directory (unless, of course, the command given changes it).
Automatic reopening will also take place if the connection was close
by the remote server for whatever reason (e.g. a timeout). It is not
available if the -1 option to zfopen or zfanon was used.

Furthermore, if the command issued is a file transfer, the connection
will be closed after the transfer is finished, hence providing a
one-shot mode for transfers. This does not apply to directory
changing or listing commands; for example a zfdir may reopen a
connection but will leave it open. Also, automatic closure will only
ever happen in the same command as automatic opening, i.e a zfdir
directly followed by a zfget will never close the connection
automatically.

Information about the previous connection is given by the zfstat
function. So, for example, if that reports:

Session: default
Not connected.
Last session: ftp.bar.com:/pub/textfiles

then the command zfget file.txt will attempt to reopen a connection
to ftp.bar.com, retrieve the file /pub/textfiles/file.txt, and
immediately close the connection again. On the other hand, zfcd ..
will open the connection in the directory /pub and leave it open.

Note that all the above is local to each session; if you return to a
previous session, the connection for that session is the one which
will be reopened.

Completion

Completion of local and remote files, directories, sessions and
bookmarks is supported. The older, compctl-style completion is
defined when zfinit is called; support for the new widget-based
completion system is provided in the function
Completion/Zsh/Command/_zftp, which should be installed with the
other functions of the completion system and hence should
automatically be available.

zsh 5.9 May 14, 2022 ZSHZFTPSYS(1)