freebsd-dev/usr.bin/fetch/fetch.1

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.\" $FreeBSD$
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.Dd March 11, 2003
.Dt FETCH 1
.Os
.Sh NAME
.Nm fetch
.Nd retrieve a file by Uniform Resource Locator
.Sh SYNOPSIS
.Nm
.Op Fl 146AFMPRUadlmnpqrsv
.Op Fl B Ar bytes
.Op Fl S Ar bytes
.Op Fl T Ar seconds
.Op Fl N Ar file
.Op Fl o Ar file
.Op Fl w Ar seconds
.Op Fl h Ar host
.Op Fl c Ar dir
.Op Fl f Ar file
.Op Ar URL ...
.Sh DESCRIPTION
The
.Nm
utility provides a command-line interface to the
.Xr fetch 3
library.
Its purpose is to retrieve the file(s) pointed to by the URL(s) on the
command line.
.Pp
The following options are available:
.Bl -tag -width Fl
.It Fl \&1
Stop and return exit code 0 at the first successfully retrieved file.
.It Fl 4
Forces
.Nm
to use IPv4 addresses only.
.It Fl 6
Forces
.Nm
to use IPv6 addresses only.
.It Fl A
Do not automatically follow ``temporary'' (302) redirects.
Some broken Web sites will return a redirect instead of a not-found
error when the requested object does not exist.
.It Fl a
Automatically retry the transfer upon soft failures.
.It Fl B Ar bytes
Specify the read buffer size in bytes.
The default is 4096 bytes.
Attempts to set a buffer size lower than this will be silently
ignored.
The number of reads actually performed is reported at verbosity level
two or higher (see the
.Fl v
flag).
.It Fl c Ar dir
The file to retrieve is in directory
.Ar dir
on the remote host.
This option is deprecated and is provided for backward compatibility
only.
.It Fl d
Use a direct connection even if a proxy is configured.
.It Fl F
In combination with the
.Fl r
flag, forces a restart even if the local and remote files have
different modification times.
Implies
.Fl R .
.It Fl f Ar file
The file to retrieve is named
.Ar file
on the remote host.
This option is deprecated and is provided for backward compatibility
only.
.It Fl h Ar host
The file to retrieve is located on the host
.Ar host .
This option is deprecated and is provided for backward compatibility
only.
.It Fl l
If the target is a file-scheme URL, make a symbolic link to the target
rather than trying to copy it.
.It Fl M
.It Fl m
Mirror mode: if the file already exists locally and has the same size
and modification time as the remote file, it will not be fetched.
Note that the
.Fl m
and
.Fl r
flags are mutually exclusive.
.It Fl N Ar file
Use
.Ar file
instead of
.Pa ~/.netrc
to look up login names and passwords for FTP sites.
See
.Xr ftp 1
for a description of the file format.
This feature is experimental.
.It Fl n
Don't preserve the modification time of the transferred file.
.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 passive FTP.
This is useful if you are behind a firewall which blocks incoming
connections.
Try this flag if
.Nm
seems to hang when retrieving FTP URLs.
.It Fl q
Quiet mode.
.It Fl R
The output files 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.
Note that the
.Fl m
and
.Fl r
flags are mutually exclusive.
.It Fl S Ar bytes
Require the file size reported by the server to match the specified
value.
If it does not, a message is printed and the file is not fetched.
If the server does not support reporting file sizes, this option is
ignored and the file is fetched unconditionally.
.It Fl s
Print the size in bytes of each requested file, without fetching it.
.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 U
When using passive FTP, allocate the port for the data connection from
the low (default) port range.
See
.Xr ip 4
for details on how to specify which port range this corresponds to.
.It Fl v
Increase verbosity level.
.It Fl w Ar seconds
When the
.Fl a
flag is specified, wait this many seconds between successive retries.
.El
.Pp
If
.Nm
receives a
.Dv SIGINFO
signal (see the
.Cm status
argument for
.Xr stty 1 ) ,
the current transfer rate statistics will be written to the
standard error output, in the same format as the standard completion
message.
.Sh DIAGNOSTICS
The
.Nm
command returns zero on success, or one on failure.
If multiple URLs are listed on the command line,
.Nm
will attempt to retrieve them each of them in turn, and return zero
only if they were all successfully retrieved.
.Sh ENVIRONMENT
.Bl -tag -width ".Ev FETCH_BIND_ADDRESS"
.It Ev FETCH_BIND_ADDRESS
Specifies a hostname or IP address to which sockets used for outgoing
connections will be bound.
.It Ev FTP_LOGIN
Default FTP login if none was provided in the URL.
.It Ev FTP_PASSIVE_MODE
If set to anything but
.Ql no ,
forces the FTP code to use passive mode.
.It Ev FTP_PASSWORD
Default FTP password if the remote server requests one and none was
provided in the URL.
.It Ev FTP_PROXY
URL of the proxy to use for FTP requests.
The document part is ignored.
FTP and HTTP proxies are supported; if no scheme is specified, FTP is
assumed.
If the proxy is an FTP proxy,
.Nm fetch
will send
.Ql user@host
as user name to the proxy, where
.Ql user
is the real user name, and
.Ql host
is the name of the FTP server.
.Pp
If this variable is set to an empty string, no proxy will be used for
FTP requests, even if the
.Ev HTTP_PROXY
variable is set.
.It Ev ftp_proxy
Same as
.Ev FTP_PROXY ,
for compatibility.
.It Ev HTTP_AUTH
Specifies HTTP authorization parameters as a colon-separated list of
items.
The first and second item are the authorization scheme and realm
respectively; further items are scheme-dependent.
Currently, only basic authorization is supported.
.Pp
Basic authorization requires two parameters: the user name and
password, in that order.
.Pp
This variable is only used if the server requires authorization and
no user name or password was specified in the URL.
.It Ev HTTP_PROXY
URL of the proxy to use for HTTP requests.
The document part is ignored.
Only HTTP proxies are supported for HTTP requests.
If no port number is specified, the default is 3128.
.Pp
Note that this proxy will also be used for FTP documents, unless the
.Ev FTP_PROXY
variable is set.
.It Ev http_proxy
Same as
.Ev HTTP_PROXY ,
for compatibility.
.It Ev HTTP_PROXY_AUTH
Specifies authorization parameters for the HTTP proxy in the same
format as the
.Ev HTTP_AUTH
variable.
.Pp
This variable is used if and only if connected to an HTTP proxy, and
is ignored if a user and/or a password were specified in the proxy
URL.
.It Ev HTTP_REFERER
Specifies the referrer URL to use for HTTP requests.
If set to
.Dq auto ,
the document URL will be used as referrer URL.
.It Ev HTTP_USER_AGENT
Specifies the User-Agent string to use for HTTP requests.
This can be useful when working with HTTP origin or proxy servers that
differentiate between user agents.
.It Ev NETRC
Specifies a file to use instead of
.Pa ~/.netrc
to look up login names and passwords for FTP sites.
See
.Xr ftp 1
for a description of the file format.
This feature is experimental.
.El
.Sh EXAMPLES
To access a proxy server on
.Pa proxy.example.com
port 8080, set the
.Ev HTTP_PROXY
environment variable in a manner similar to this:
.Pp
.Dl HTTP_PROXY=<A HREF="http://proxy.example.com:8080">http://proxy.example.com:8080</A>
.Pp
If the proxy server requires authentication, there are
two options available for passing the authentication data.
The first method is by using the proxy URL:
.Pp
.Dl HTTP_PROXY=http://<user>:<pwd>@proxy.example.com:8080
.Pp
The second method is by using the
.Ev HTTP_PROXY_AUTH
environment variable:
.Bd -literal -offset indent
HTTP_PROXY=<A HREF="http://proxy.example.com:8080">http://proxy.example.com:8080</A>
HTTP_PROXY_AUTH=basic:*:<user>:<pwd>
.Ed
.Sh SEE ALSO
.Xr fetch 3
.Sh HISTORY
The
.Nm
command appeared in
.Fx 2.1.5 .
This implementation first appeared in
.Fx 4.1 .
.Sh AUTHORS
.An -nosplit
The original implementation of
.Nm
was done by
.An Jean-Marc Zucconi Aq jmz@FreeBSD.org .
It was extensively re-worked for
.Fx 2.2
by
.An Garrett Wollman Aq wollman@FreeBSD.org ,
and later completely rewritten to use the
.Xr fetch 3
library by
.An Dag-Erling Sm\(/orgrav Aq des@FreeBSD.org .
.Sh NOTES
The
.Fl b
and
.Fl t
options are no longer supported and will generate warnings.
They were workarounds for bugs in other OSes which this implementation
does not trigger.
.Pp
One cannot both use the
.Fl h ,
.Fl c
and
.Fl f
options and specify URLs on the command line.