xref: /freebsd/usr.bin/fetch/fetch.1 (revision 2494e810b8339b6e8870322fd08304d5e7775218)

.\" $FreeBSD$
.Dd July 2, 1996
.Dt FETCH 1
.Os
.Sh NAME
.Nm fetch
.Nd retrieve a file by Uniform Resource Locator
.Sh SYNOPSIS
.Nm fetch
.Op Fl MPamnpqr
.Op Fl o Ar file
.Ar URL
.Nm fetch
.Op Fl MPRmnpqr
.Op Fl o Ar file
.Op Fl c Ar dir
.Fl f Ar file
.Fl h Ar host
.Sh DESCRIPTION
.Nm fetch
allows a user to transfer files from a remote network site using
either the
.Em ftp
or the
.Em http
protocol. In the first form of the command, the
.Ar URL
may be of the form
.Li http://site.domain/path/to/the/file
or
.Li ftp://site.domain/path/to/the/file.
To denote a local filename to be copied or linked to (see the
.Fl l
flag below), the
.Em file:/path/to/the/file
URL form is used.
.Pp
The second form of the command can be used to get a file using the
.Tn FTP
protocol, specifying the file name and the remote host with the
.Fl h
and the
.Fl f
flags.
.Pp
The following options are available:
.Bl -tag -width Fl -compact
.It Fl a
Automatically retry the transfer upon soft failures.
.It Fl c Ar dir
The file to retrieve is in directory
.Ar dir
on the remote host.
.It Fl f Ar file
The file to retrieve is named
.Ar file
on the remote host.
.It Fl h Ar host
The file to retrieve is located on the host
.Ar host .
.It Fl l
If target is a
.Ar file:/
style of URL, make a link to the target rather than trying
to copy it.
.It Fl M
.It Fl m
Mirror mode: Set the modification time of the file so that it is
identical to the modification time of the file at the remote host.
If the file already exists on the local host and is identical (as
gauged by size and modification time), no transfer is done.
.It Fl n
Don't preserve the modtime of the transfered file, use the current time.
.It Fl o Ar file
Set the output file name to
.Ar file .
By default, a ``pathname'' is extracted from the specified URI, and
its basename is used as the name of the output file.  A
.Ar file
argument of
.Sq Li \&-
indicates that results are to be directed to the standard output.
.It Fl P
.It Fl p
Use the passive mode of the
.Tn FTP
protocol.  This is useful for crossing certain sorts of firewalls.
.It Fl q
Quiet mode. Do not report transfer progress on the terminal.
.It Fl R
The filenames specified are ``precious'', and should not be deleted
under any circumstances, even if the transfer failed or was incomplete.
.It Fl r
Restart a previously interrupted transfer.
.It Fl T Ar seconds
Set timeout value to
.Ar seconds.
Overrides the environment variables
.Ev FTP_TIMEOUT
for ftp transfers or
.Ev HTTP_TIMEOUT
for http transfers if set.
.It Fl v
Increase verbosity.  More
.Fl v Ns \&'s
result in more information.
.El
.Pp
Many options are also controlled solely by the environment (this is a
bug).
.Sh PROXY SERVERS
Many sites use application gateways (``proxy servers'') in their
firewalls in order to allow communication across the firewall using a
trusted protocol.  The
.Nm fetch
program can use both the
.Tn FTP
and the
.Tn HTTP
protocol with a proxy server.
.Tn FTP
proxy servers can only relay
.Tn FTP
requests;
.Tn HTTP
proxy servers can relay both
.Tn FTP
and
.Tn HTTP
requests.
A proxy server can be configured by defining an environment variable
named
.Dq Va PROTO Ns Ev _PROXY ,
where
.Va PROTO
is the name of the protocol in upper case.  The value of the
environment variable specifies a hostname, optionally followed by a
colon and a port number.
.Pp
The
.Tn FTP
proxy client specifies
.Dq anonymous
as its user name, and passes the remote user name and host as the
.Tn FTP
session's password, in the form
.Dq Va remoteuser Ns Li \&@ Va remotehost .
The
.Tn HTTP
proxy client simply passes the originally-requested URI to the remote
server in an
.Tn HTTP
.Dq Li GET
request.  HTTP proxy authentication is not yet implemented.
When multiple proxy protcols are configured,
.Nm
will prefer
.Tn HTTP .
.Sh ENVIRONMENT
.Bl -tag -width FTP_PASSIVE_MODE -offset indent
.It Ev FTP_TIMEOUT
maximum time, in seconds, to wait before aborting an
.Tn FTP
connection.
.It Ev HTTP_TIMEOUT
maximum time, in seconds, to wait before aborting an
.Tn HTTP
connection.
.It Ev FTP_LOGIN
the login name used for
.Tn FTP
transfers (default
.Dq Li anonymous )
.It Ev FTP_PASSWORD
the password used for
.Tn FTP
transfers (default
.Dq Va yourname Ns Li \&@ Ns Va yourhost )
.It Ev FTP_PASSIVE_MODE
force the use of passive mode FTP
.It Ev HTTP_PROXY
the address of a proxy server which understands
.Tn HTTP
.It Ev FTP_PROXY
the address of a proxy server which understands
.Tn FTP
.Sh SEE ALSO
.Xr ftp 1 ,
.Xr tftp 1
.Sh HISTORY
The
.Nm fetch
command appeared in
.Fx 2.1.5 .
.Sh AUTHORS
The original implementation of
.Nm
was done by Jean-Marc Zucconi.  It was extensively re-worked for
.Fx 3.0
by Garrett Wollman.
.Sh BUGS
There are too many environment variables and command-line options.
.Pp
The
.Fl a
option is only implemented for certain kinds of
.Tn HTTP
failures, and no
.Tn FTP
failures.
.Pp
.Tn HTTP
authentication is not yet implememnted.