fetch1

Usage

Overview

The fetch utility provides a command-line interface to the fetch(3) library. Its purpose is to retrieve the file(s) pointed to by the URL(s) on the command line.

The following options are available:

-1, --one-file

Stop and return exit code 0 at the first successfully retrieved file.

-4, --ipv4-only

Forces fetch to use IPv4 addresses only.

-6, --ipv6-only

Forces fetch to use IPv6 addresses only.

-A, --no-redirect

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.

-a, --retry

Automatically retry the transfer upon soft failures.

-B bytes, --buffer-size=bytes

Specify the read buffer size in bytes. The default is 16,384 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 -v flag).

--bind-address=host

Specifies a hostname or IP address to which sockets used for outgoing connections will be bound.

-c dir

The file to retrieve is in directory dir on the remote host. This option is deprecated and is provided for backward compatibility only.

--ca-cert=file

[SSL] Path to certificate bundle containing trusted CA certificates. Otherwise, OpenSSL's default CA cert and path settings apply.

--ca-path=dir

[SSL] The directory dir contains trusted CA hashes.

--cert=file

[SSL] file is a PEM encoded client certificate/key which will be used in client certificate authentication.

--crl=file

[SSL] Points to certificate revocation list file, which has to be in PEM format and may contain peer certificates that have been revoked.

-d, --direct

Use a direct connection even if a proxy is configured.

-F, --force-restart

In combination with the -r flag, forces a restart even if the local and remote files have different modification times. Implies -R.

-f file

The file to retrieve is named file on the remote host. This option is deprecated and is provided for backward compatibility only.

-h host

The file to retrieve is located on the host host. This option is deprecated and is provided for backward compatibility only.

-i file, --if-modified-since=file

If-Modified-Since mode: the remote file will only be retrieved if it is newer than file on the local host. (HTTP only)

--key=file

[SSL] file is a PEM encoded client key that will be used in client certificate authentication in case key and client certificate are stored separately.

-l, --symlink

If the target is a file-scheme URL, make a symbolic link to the target rather than trying to copy it.

-M

-m, --mirror

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 -m and -r flags are mutually exclusive.

-N file, --netrc=file

Use file instead of ~/.netrc to look up login names and passwords for FTP sites. See ftp(1) for a description of the file format. This feature is experimental.

-n, --no-mtime

Do not preserve the modification time of the transferred file.

--no-passive

Forces the FTP code to use active mode.

--no-proxy=list

Either a single asterisk, which disables the use of proxies altogether, or a comma- or whitespace-separated list of hosts for which proxies should not be used.

--no-sslv3

[SSL] Do not allow SSL version 3 when negotiating the connection. This option is deprecated and is provided for backward compatibility only. SSLv3 is disabled by default. Set SSL_ALLOW_SSL3 to change this behavior.

--no-tlsv1

[SSL] Do not allow TLS version 1 when negotiating the connection.

--no-verify-hostname

[SSL] Do not verify that the hostname matches the subject of the certificate presented by the server.

--no-verify-peer

[SSL] Do not verify the peer certificate against trusted CAs.

-o file, --output=file

Set the output file name to file. By default, a ``pathname'' is extracted from the specified URI, and its basename is used as the name of the output file. A file argument of ‘-’ indicates that results are to be directed to the standard output. If the file argument is a directory, fetched file(s) will be placed within the directory, with name(s) selected as in the default behaviour.

-P

-p, --passive

Use passive FTP. These flags have no effect, since passive FTP is the default, but are provided for compatibility with earlier versions where active FTP was the default. To force active mode, use the --no-passive flag or set the FTP_PASSIVE_MODE environment variable to ‘NO’.

--referer=URL

Specifies the referrer URL to use for HTTP requests. If URL is set to “auto”, the document URL will be used as referrer URL.

-q, --quiet

Quiet mode.

-R, --keep-output

The output files are precious, and should not be deleted under any circumstances, even if the transfer failed or was incomplete.

-r, --restart

Restart a previously interrupted transfer. Note that the -m and -r flags are mutually exclusive.

-S bytes, --require-size=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.

-s, --print-size

Print the size in bytes of each requested file, without fetching it.

-T seconds, --timeout=seconds

Set the network timeout to seconds. Overrides the environment variables FTP_TIMEOUT for FTP transfers or HTTP_TIMEOUT for HTTP transfers if set.

-U, --passive-portrange-default

When using passive FTP, allocate the port for the data connection from the low (default) port range. See ip(4) for details on how to specify which port range this corresponds to.

--user-agent=agent-string

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.

-v, --verbose

Increase verbosity level.

-w seconds, --retry-delay=seconds

When the -a flag is specified, wait this many seconds between successive retries.

If fetch receives a SIGINFO signal (see the status argument for stty(1)), the current transfer rate statistics will be written to the standard error output, in the same format as the standard completion message.

Environment

FTP_TIMEOUT

Maximum time, in seconds, to wait before giving up on a stalled FTP transfer.

HTTP_TIMEOUT

Maximum time, in seconds, to wait before giving up on a stalled HTTP transfer.

See fetch(3) for a description of additional environment variables, including FETCH_BIND_ADDRESS, FTP_LOGIN, FTP_PASSIVE_MODE, FTP_PASSWORD, FTP_PROXY, ftp_proxy, HTTP_ACCEPT, HTTP_AUTH, HTTP_PROXY, http_proxy, HTTP_PROXY_AUTH, HTTP_REFERER, HTTP_USER_AGENT, NETRC, NO_PROXY, no_proxy, SSL_CA_CERT_FILE, SSL_CA_CERT_PATH, SSL_CLIENT_CERT_FILE, SSL_CLIENT_KEY_FILE, SSL_CRL_FILE, SSL_ALLOW_SSL3, SSL_NO_TLS1, SSL_NO_TLS1_1, SSL_NO_TLS1_2, SSL_NO_VERIFY_HOSTNAME and SSL_NO_VERIFY_PEER.

Exit status

The fetch command returns zero on success, or one on failure. If multiple URLs are listed on the command line, fetch will attempt to retrieve each one of them in turn, and will return zero only if they were all successfully retrieved.

If the -i argument is used and the remote file is not newer than the specified file then the command will still return success, although no file is transferred.

Examples

Silently try to fetch the URLs passed as parameters. The first one will fail. If the second URL succeeds the third one will not be tried:

$ fetch -1 -q https://www.freebsd.org/bad.html \
	ftp.freebsd.org/pub/FreeBSD/README.TXT \
	https://www.fake.url
fetch: https://www.freebsd.org/bad.html: Not Found

Be verbose when retrieving the README.TXT file:

$ fetch -v ftp.freebsd.org/pub/FreeBSD/README.TXT
resolving server address: ftp.freebsd.org:80
requesting http://ftp.freebsd.org/pub/FreeBSD/README.TXT
local size / mtime: 4259 / 1431015519
remote size / mtime: 4259 / 1431015519
README.TXT                                            4259  B   44 MBps    00s

Quietly save the README.TXT file as myreadme.txt and do not delete the output file under any circumstances:

fetch -o myreadme.txt -q -R ftp.freebsd.org/pub/FreeBSD/README.TXT

Print the size of the requested file and identify the request with a custom user agent string:

$ fetch -s ftp.freebsd.org/pub/FreeBSD/README.TXT
--user-agent="Mozilla/5.0 (X11; FreeBSD x86_64; rv:78.0) Gecko/20100101"
3513231

Restart the transfer of the README.TXT file and retry the transfer upon soft failures:

$ fetch -a -r http://ftp.freebsd.org/pub/FreeBSD/README.TXT

Notes

The -b and -t options are no longer supported and will generate warnings. They were workarounds for bugs in other OSes which this implementation does not trigger.

One cannot both use the -h, -c and -f options and specify URLs on the command line.