import libfetch-2.38 from NetBSD

ftp://ftp.fu-berlin.de/unix/NetBSD/packages/current-src/pkgsrc/net/libfetch/files

libfetch comes (at least) in netbsd and freebsd flavors which
differing functionality. Alpine and Arch package netbsd one,
but it's not widely packaged across other distributions.

We need NetBSD version as it does not use funopen(3) which is not
supported in musl, and supports connection pooling.

FreeBSD seems to be the orignal and better maintained version
with support for SSL CAs, client certificate authentication,
proxy authentication, and improved http redirect handling.

So this imports NetBSD version, and future commits will pick up
the needed improvements from FreeBSD tree.

Incidentally, this also fixes #7857 and likes for good.

1 files changed, 781 insertions, 0 deletions

diff --git a/libfetch/fetch.3 b/libfetch/fetch.3
new file mode 100644
index 0000000..bb58071
--- /dev/null
+++ b/libfetch/fetch.3
@@ -0,0 +1,781 @@
+.\"-
+.\" Copyright (c) 1998-2004 Dag-Erling Coïdan Smørgrav
+.\" Copyright (c) 2010 Joerg Sonnenberger <joerg@NetBSD.org>
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD: fetch.3,v 1.64 2007/12/18 11:03:26 des Exp $
+.\" $NetBSD: fetch.3,v 1.17 2016/05/31 18:02:36 abhinav Exp $
+.\"
+.Dd January 22, 2010
+.Dt FETCH 3
+.Os
+.Sh NAME
+.Nm fetchMakeURL ,
+.Nm fetchParseURL ,
+.Nm fetchCopyURL ,
+.Nm fetchFreeURL ,
+.Nm fetchXGetURL ,
+.Nm fetchGetURL ,
+.Nm fetchPutURL ,
+.Nm fetchStatURL ,
+.Nm fetchListURL ,
+.Nm fetchXGet ,
+.Nm fetchGet ,
+.Nm fetchPut ,
+.Nm fetchStat ,
+.Nm fetchList ,
+.Nm fetchXGetFile ,
+.Nm fetchGetFile ,
+.Nm fetchPutFile ,
+.Nm fetchStatFile ,
+.Nm fetchListFile ,
+.Nm fetchXGetHTTP ,
+.Nm fetchGetHTTP ,
+.Nm fetchPutHTTP ,
+.Nm fetchStatHTTP ,
+.Nm fetchListHTTP ,
+.Nm fetchXGetFTP ,
+.Nm fetchGetFTP ,
+.Nm fetchPutFTP ,
+.Nm fetchStatFTP ,
+.Nm fetchListFTP
+.Nm fetchInitURLList ,
+.Nm fetchFreeURLList ,
+.Nm fetchUnquotePath ,
+.Nm fetchUnquoteFilename ,
+.Nm fetchStringifyURL ,
+.Nm fetchConnectionCacheInit ,
+.Nm fetchConnectionCacheClose ,
+.Nm fetch
+.Nd file transfer functions
+.Sh LIBRARY
+.Lb libfetch
+.Sh SYNOPSIS
+.In stdio.h
+.In fetch.h
+.Ft struct url *
+.Fn fetchMakeURL "const char *scheme" "const char *host" "int port" "const char *doc" "const char *user" "const char *pwd"
+.Ft struct url *
+.Fn fetchParseURL "const char *URL"
+.Ft struct url *
+.Fn fetchCopyURL "const struct url *u"
+.Ft void
+.Fn fetchFreeURL "struct url *u"
+.Ft fetchIO *
+.Fn fetchXGetURL "const char *URL" "struct url_stat *us" "const char *flags"
+.Ft fetchIO *
+.Fn fetchGetURL "const char *URL" "const char *flags"
+.Ft fetchIO *
+.Fn fetchPutURL "const char *URL" "const char *flags"
+.Ft int
+.Fn fetchStatURL "const char *URL" "struct url_stat *us" "const char *flags"
+.Ft int
+.Fn fetchListURL "struct url_list *list" "const char *URL" "const char *pattern" "const char *flags"
+.Ft fetchIO *
+.Fn fetchXGet "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft fetchIO *
+.Fn fetchGet "struct url *u" "const char *flags"
+.Ft fetchIO *
+.Fn fetchPut "struct url *u" "const char *flags"
+.Ft int
+.Fn fetchStat "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft int
+.Fn fetchList "struct url_list *list" "struct url *u" "const char *pattern" "const char *flags"
+.Ft fetchIO *
+.Fn fetchXGetFile "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft fetchIO *
+.Fn fetchGetFile "struct url *u" "const char *flags"
+.Ft fetchIO *
+.Fn fetchPutFile "struct url *u" "const char *flags"
+.Ft int
+.Fn fetchStatFile "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft int
+.Fn fetchListFile "struct url_list *list" "struct url *u" "const char *pattern" "const char *flags"
+.Ft fetchIO *
+.Fn fetchXGetHTTP "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft fetchIO *
+.Fn fetchGetHTTP "struct url *u" "const char *flags"
+.Ft fetchIO *
+.Fn fetchPutHTTP "struct url *u" "const char *flags"
+.Ft int
+.Fn fetchStatHTTP "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft int
+.Fn fetchListHTTP "struct url_list *list" "struct url *u" "const char *pattern" "const char *flags"
+.Ft fetchIO *
+.Fn fetchXGetFTP "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft fetchIO *
+.Fn fetchGetFTP "struct url *u" "const char *flags"
+.Ft fetchIO *
+.Fn fetchPutFTP "struct url *u" "const char *flags"
+.Ft int
+.Fn fetchStatFTP "struct url *u" "struct url_stat *us" "const char *flags"
+.Ft int
+.Fn fetchListFTP "struct url_list *list" "struct url *u" "const char *pattern" "const char *flags"
+.Ft void
+.Fn fetchInitURLList "struct url_list *ul"
+.Ft int
+.Fn fetchAppendURLList "struct url_list *dst" "const struct url_list *src"
+.Ft void
+.Fn fetchFreeURLList "struct url_list *ul"
+.Ft char *
+.Fn fetchUnquotePath "struct url *u"
+.Ft char *
+.Fn fetchUnquoteFilename "struct url *u"
+.Ft char *
+.Fn fetchStringifyURL "const struct url *u"
+.Ft void
+.Fn fetchConnectionCacheInit "int global" "int per_host"
+.Ft void
+.Fn fetchConnectionCacheClose "void"
+.Sh DESCRIPTION
+These functions implement a high-level library for retrieving and
+uploading files using Uniform Resource Locators (URLs).
+.Pp
+.Fn fetchParseURL
+takes a URL in the form of a null-terminated string and splits it into
+its components function according to the Common Internet Scheme Syntax
+detailed in RFC 1738.
+A regular expression which produces this syntax is:
+.Bd -literal -offset indent
+\*[Lt]scheme\*[Gt]:(//(\*[Lt]user\*[Gt](:\*[Lt]pwd\*[Gt])?@)?\*[Lt]host\*[Gt](:\*[Lt]port\*[Gt])?)?/(\*[Lt]doc\*[Gt])?
+.Ed
+.Pp
+If the URL does not seem to begin with a scheme name, it is assumed to be a local path.
+Only absolute path names are accepted.
+.Pp
+Note that some components of the URL are not necessarily relevant to
+all URL schemes.
+For instance, the file scheme only needs the
+.Aq scheme
+and
+.Aq doc
+components.
+.Fn fetchParseURL
+quotes any unsafe character in the URL automatically.
+This is not done by
+.Fn fetchMakeURL .
+.Fn fetchCopyURL
+copies an existing
+.Vt url
+structure.
+.Pp
+.Fn fetchMakeURL ,
+.Fn fetchParseURL ,
+and
+.Fn fetchCopyURL
+return a pointer to a
+.Vt url
+structure, which is defined as follows in
+.In fetch.h :
+.Bd -literal
+#define URL_SCHEMELEN 16
+#define URL_USERLEN 256
+#define URL_PWDLEN 256
+#define URL_HOSTLEN 255
+
+struct url {
+    char	 scheme[URL_SCHEMELEN + 1];
+    char	 user[URL_USERLEN + 1];
+    char	 pwd[URL_PWDLEN + 1];
+    char	 host[URL_HOSTLEN + 1];
+    int		 port;
+    char	*doc;
+    off_t	 offset;
+    size_t	 length;
+    time_t	 last_modified;
+};
+.Ed
+.Pp
+The pointer returned by
+.Fn fetchMakeURL ,
+.Fn fetchCopyURL ,
+and
+.Fn fetchParseURL
+should be freed using
+.Fn fetchFreeURL .
+The size of
+.Vt struct URL
+is not part of the ABI.
+.Pp
+.Fn fetchXGetURL ,
+.Fn fetchGetURL ,
+and
+.Fn fetchPutURL
+constitute the recommended interface to the
+.Nm fetch
+library.
+They examine the URL passed to them to determine the transfer
+method, and call the appropriate lower-level functions to perform the
+actual transfer.
+.Fn fetchXGetURL
+also returns the remote document's metadata in the
+.Vt url_stat
+structure pointed to by the
+.Fa us
+argument.
+.Pp
+The
+.Fa flags
+argument is a string of characters which specify transfer options.
+The
+meaning of the individual flags is scheme-dependent, and is detailed
+in the appropriate section below.
+.Pp
+.Fn fetchStatURL
+attempts to obtain the requested document's metadata and fill in the
+structure pointed to by its second argument.
+The
+.Vt url_stat
+structure is defined as follows in
+.In fetch.h :
+.Bd -literal
+struct url_stat {
+    off_t	 size;
+    time_t	 atime;
+    time_t	 mtime;
+};
+.Ed
+.Pp
+If the size could not be obtained from the server, the
+.Fa size
+field is set to \-1.
+If the modification time could not be obtained from the server, the
+.Fa mtime
+field is set to the epoch.
+If the access time could not be obtained from the server, the
+.Fa atime
+field is set to the modification time.
+.Pp
+.Fn fetchListURL
+attempts to list the contents of the directory pointed to by the URL provided.
+The pattern can be a simple glob-like expression as hint.
+Callers should not depend on the server to filter names.
+If successful, it appends the list of entries to the
+.Vt url_list
+structure.
+The
+.Vt url_list
+structure is defined as follows in
+.In fetch.h :
+.Bd -literal
+struct url_list {
+    size_t	length;
+    size_t	alloc_size;
+    struct url	*urls;
+};
+.Ed
+.Pp
+The list should be initialized by calling
+.Fn fetchInitURLList
+and the entries be freed by calling
+.Fn fetchFreeURLList .
+The function
+.Fn fetchAppendURLList
+can be used to append one URL lists to another.
+If the
+.Ql c
+(cache result) flag is specified, the library is allowed to internally
+cache the result.
+.Pp
+.Fn fetchStringifyURL
+returns the URL as string.
+.Fn fetchUnquotePath
+returns the path name part of the URL with any quoting undone.
+Query arguments and fragment identifiers are not included.
+.Fn fetchUnquoteFilename
+returns the last component of the path name as returned by
+.Fn fetchUnquotePath .
+.Fn fetchStringifyURL ,
+.Fn fetchUnquotePath ,
+and
+.Fn fetchUnquoteFilename
+return a string that should be deallocated with
+.Fn free
+after use.
+.Pp
+.Fn fetchConnectionCacheInit
+enables the connection cache.
+The first argument specifies the global limit on cached connections.
+The second argument specifies the host limit.
+Entries are considered to specify the same host, if the host name
+from the URL is identical, indepent of the address or address family.
+.Fn fetchConnectionCacheClose
+flushed the connection cache and closes all cached connections.
+.Pp
+.Fn fetchXGet ,
+.Fn fetchGet ,
+.Fn fetchPut ,
+and
+.Fn fetchStat
+are similar to
+.Fn fetchXGetURL ,
+.Fn fetchGetURL ,
+.Fn fetchPutURL ,
+and
+.Fn fetchStatURL ,
+except that they expect a pre-parsed URL in the form of a pointer to
+a
+.Vt struct url
+rather than a string.
+.Pp
+All of the
+.Fn fetchXGetXXX ,
+.Fn fetchGetXXX ,
+and
+.Fn fetchPutXXX
+functions return a pointer to a stream which can be used to read or
+write data from or to the requested document, respectively.
+Note that
+although the implementation details of the individual access methods
+vary, it can generally be assumed that a stream returned by one of the
+.Fn fetchXGetXXX
+or
+.Fn fetchGetXXX
+functions is read-only, and that a stream returned by one of the
+.Fn fetchPutXXX
+functions is write-only.
+.Sh PROTOCOL INDEPENDENT FLAGS
+If the
+.Ql i
+(if-modified-since) flag is specified, the library will try to fetch
+the content only if it is newer than
+.Va last_modified .
+For HTTP an
+.Li If-Modified-Since
+HTTP header is sent.
+For FTP a
+.Li MTDM
+command is sent first and compared locally.
+For FILE the source file is compared.
+.Sh FILE SCHEME
+.Fn fetchXGetFile ,
+.Fn fetchGetFile ,
+and
+.Fn fetchPutFile
+provide access to documents which are files in a locally mounted file
+system.
+Only the
+.Aq document
+component of the URL is used.
+.Pp
+.Fn fetchXGetFile
+and
+.Fn fetchGetFile
+do not accept any flags.
+.Pp
+.Fn fetchPutFile
+accepts the
+.Ql a
+(append to file) flag.
+If that flag is specified, the data written to
+the stream returned by
+.Fn fetchPutFile
+will be appended to the previous contents of the file, instead of
+replacing them.
+.Sh FTP SCHEME
+.Fn fetchXGetFTP ,
+.Fn fetchGetFTP ,
+and
+.Fn fetchPutFTP
+implement the FTP protocol as described in RFC 959.
+.Pp
+By default
+.Nm libfetch
+will attempt to use passive mode first and only fallback to active mode
+if the server reports a syntax error.
+If the
+.Ql a
+(active) flag is specified, a passive connection is not tried and active mode
+is used directly.
+.Pp
+If the
+.Ql l
+(low) flag is specified, data sockets will be allocated in the low (or
+default) port range instead of the high port range (see
+.Xr ip 4 ) .
+.Pp
+If the
+.Ql d
+(direct) flag is specified,
+.Fn fetchXGetFTP ,
+.Fn fetchGetFTP ,
+and
+.Fn fetchPutFTP
+will use a direct connection even if a proxy server is defined.
+.Pp
+If no user name or password is given, the
+.Nm fetch
+library will attempt an anonymous login, with user name "anonymous"
+and password "anonymous@\*[Lt]hostname\*[Gt]".
+.Sh HTTP SCHEME
+The
+.Fn fetchXGetHTTP ,
+.Fn fetchGetHTTP ,
+and
+.Fn fetchPutHTTP
+functions implement the HTTP/1.1 protocol.
+With a little luck, there is
+even a chance that they comply with RFC 2616 and RFC 2617.
+.Pp
+If the
+.Ql d
+(direct) flag is specified,
+.Fn fetchXGetHTTP ,
+.Fn fetchGetHTTP ,
+and
+.Fn fetchPutHTTP
+will use a direct connection even if a proxy server is defined.
+.Pp
+Since there seems to be no good way of implementing the HTTP PUT
+method in a manner consistent with the rest of the
+.Nm fetch
+library,
+.Fn fetchPutHTTP
+is currently unimplemented.
+.Sh AUTHENTICATION
+Apart from setting the appropriate environment variables and
+specifying the user name and password in the URL or the
+.Vt struct url ,
+the calling program has the option of defining an authentication
+function with the following prototype:
+.Pp
+.Ft int
+.Fn myAuthMethod "struct url *u"
+.Pp
+The callback function should fill in the
+.Fa user
+and
+.Fa pwd
+fields in the provided
+.Vt struct url
+and return 0 on success, or any other value to indicate failure.
+.Pp
+To register the authentication callback, simply set
+.Va fetchAuthMethod
+to point at it.
+The callback will be used whenever a site requires authentication and
+the appropriate environment variables are not set.
+.Pp
+This interface is experimental and may be subject to change.
+.Sh RETURN VALUES
+.Fn fetchParseURL
+returns a pointer to a
+.Vt struct url
+containing the individual components of the URL.
+If it is
+unable to allocate memory, or the URL is syntactically incorrect,
+.Fn fetchParseURL
+returns a
+.Dv NULL
+pointer.
+.Pp
+The
+.Fn fetchStat
+functions return 0 on success and \-1 on failure.
+.Pp
+All other functions return a stream pointer which may be used to
+access the requested document, or
+.Dv NULL
+if an error occurred.
+.Pp
+The following error codes are defined in
+.In fetch.h :
+.Bl -tag -width 18n
+.It Bq Er FETCH_ABORT
+Operation aborted
+.It Bq Er FETCH_AUTH
+Authentication failed
+.It Bq Er FETCH_DOWN
+Service unavailable
+.It Bq Er FETCH_EXISTS
+File exists
+.It Bq Er FETCH_FULL
+File system full
+.It Bq Er FETCH_INFO
+Informational response
+.It Bq Er FETCH_MEMORY
+Insufficient memory
+.It Bq Er FETCH_MOVED
+File has moved
+.It Bq Er FETCH_NETWORK
+Network error
+.It Bq Er FETCH_OK
+No error
+.It Bq Er FETCH_PROTO
+Protocol error
+.It Bq Er FETCH_RESOLV
+Resolver error
+.It Bq Er FETCH_SERVER
+Server error
+.It Bq Er FETCH_TEMP
+Temporary error
+.It Bq Er FETCH_TIMEOUT
+Operation timed out
+.It Bq Er FETCH_UNAVAIL
+File is not available
+.It Bq Er FETCH_UNKNOWN
+Unknown error
+.It Bq Er FETCH_URL
+Invalid URL
+.El
+.Pp
+The accompanying error message includes a protocol-specific error code
+and message, e.g.\& "File is not available (404 Not Found)"
+.Sh ENVIRONMENT
+.Bl -tag -width ".Ev FETCH_BIND_ADDRESS"
+.It Ev FETCH_BIND_ADDRESS
+Specifies a host name 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 libfetch
+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.
+.It Ev NO_PROXY
+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.
+.It Ev no_proxy
+Same as
+.Ev NO_PROXY ,
+for compatibility.
+.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=http://proxy.example.com:8080
+.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://\*[Lt]user\*[Gt]:\*[Lt]pwd\*[Gt]@proxy.example.com:8080
+.Pp
+The second method is by using the
+.Ev HTTP_PROXY_AUTH
+environment variable:
+.Bd -literal -offset indent
+HTTP_PROXY=http://proxy.example.com:8080
+HTTP_PROXY_AUTH=basic:*:\*[Lt]user\*[Gt]:\*[Lt]pwd\*[Gt]
+.Ed
+.Pp
+To disable the use of a proxy for an HTTP server running on the local
+host, define
+.Ev NO_PROXY
+as follows:
+.Bd -literal -offset indent
+NO_PROXY=localhost,127.0.0.1
+.Ed
+.Sh SEE ALSO
+.\" .Xr fetch 1 ,
+.\" .Xr ftpio 3 ,
+.Xr ftp 1 ,
+.Xr ip 4
+.Rs
+.%A J. Postel
+.%A J. K. Reynolds
+.%D October 1985
+.%B File Transfer Protocol
+.%O RFC 959
+.Re
+.Rs
+.%A P. Deutsch
+.%A A. Emtage
+.%A A. Marine
+.%D May 1994
+.%T How to Use Anonymous FTP
+.%O RFC 1635
+.Re
+.Rs
+.%A T. Berners-Lee
+.%A L. Masinter
+.%A M. McCahill
+.%D December 1994
+.%T Uniform Resource Locators (URL)
+.%O RFC 1738
+.Re
+.Rs
+.%A R. Fielding
+.%A J. Gettys
+.%A J. Mogul
+.%A H. Frystyk
+.%A L. Masinter
+.%A P. Leach
+.%A T. Berners-Lee
+.%D January 1999
+.%B Hypertext Transfer Protocol -- HTTP/1.1
+.%O RFC 2616
+.Re
+.Rs
+.%A J. Franks
+.%A P. Hallam-Baker
+.%A J. Hostetler
+.%A S. Lawrence
+.%A P. Leach
+.%A A. Luotonen
+.%A L. Stewart
+.%D June 1999
+.%B HTTP Authentication: Basic and Digest Access Authentication
+.%O RFC 2617
+.Re
+.Sh HISTORY
+The
+.Nm fetch
+library first appeared in
+.Fx 3.0 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm fetch
+library was mostly written by
+.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org
+with numerous suggestions from
+.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org ,
+.An Eugene Skepner Aq Mt eu@qub.com
+and other
+.Fx
+developers.
+It replaces the older
+.Nm ftpio
+library written by
+.An Poul-Henning Kamp Aq Mt phk@FreeBSD.org
+and
+.An Jordan K. Hubbard Aq Mt jkh@FreeBSD.org .
+.Pp
+This manual page was written by
+.An Dag-Erling Sm\(/orgrav Aq Mt des@FreeBSD.org .
+.Sh BUGS
+Some parts of the library are not yet implemented.
+The most notable
+examples of this are
+.Fn fetchPutHTTP
+and FTP proxy support.
+.Pp
+There is no way to select a proxy at run-time other than setting the
+.Ev HTTP_PROXY
+or
+.Ev FTP_PROXY
+environment variables as appropriate.
+.Pp
+.Nm libfetch
+does not understand or obey 305 (Use Proxy) replies.
+.Pp
+Error numbers are unique only within a certain context; the error
+codes used for FTP and HTTP overlap, as do those used for resolver and
+system errors.
+For instance, error code 202 means "Command not
+implemented, superfluous at this site" in an FTP context and
+"Accepted" in an HTTP context.
+.Pp
+.Fn fetchStatFTP
+does not check that the result of an MDTM command is a valid date.
+.Pp
+The man page is incomplete, poorly written and produces badly
+formatted text.
+.Pp
+The error reporting mechanism is unsatisfactory.
+.Pp
+Some parts of the code are not fully reentrant.