add docs for TEXLIVE_DOWNLOADER, _COMPRESSOR, and selection order

git-svn-id: svn://tug.org/texlive/trunk@47874 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 78 insertions, 3 deletions

diff --git a/Master/install-tl b/Master/install-tl
index 1fbe07d9c39..9454e4e544e 100755
--- a/Master/install-tl
+++ b/Master/install-tl
@@ -2589,9 +2589,8 @@ simplified Chinese (zh_CN), and traditional Chinese (zh_TW).
 
 Specify the package repository to be used as the source of the
 installation, either a local directory via C</path/to/directory> or a
-C<file:/> url, or a network location via a C<http://>, C<https://>, or
-C<ftp://> url.  (No other protocols are supported, and C<https://> may
-not work on all platforms.)
+C<file:/> url, or a network location. See L</SUPPORTED URL SCHEMATA>
+for details.
 
 The default is to pick a mirror automatically, using
 L<http://mirror.ctan.org/systems/texlive/tlnet>; the chosen mirror is
@@ -2908,6 +2907,41 @@ written, the names above are always used.
 For more details on all of the above options, consult the TeX Live
 installation manual, linked from L<http://tug.org/texlive/doc>.
 
+=head1 SUPPORTED URL SCHEMATA
+
+The following URL schemata are supported
+
+=over 4
+
+=item C<http://server/path/to/tlnet>
+
+Standard schema, is supported without any restrictions. If the (default)
+LWP method is used, this schema supports persistent connections.
+
+=item C<ftp://server/path/to/tlnet>
+
+If the (default) LWP method is used, this schema supports persistent connections.
+
+=item C<https://server/path/to/tlnet>
+
+If the (default) LWP method is used, this schema supports persistent connections.
+Some versions of C<wget> do not support this schema. Furthermore, even if
+C<wget> supports https, it might check the certificate. C<curl> generally 
+supports https.
+
+=item C<user@machine:/path/to/tlnet>
+
+=item C<scp://user@machine/path/to/tlnet>
+
+=item C<ssh://user@machine/path/to/tlnet>
+
+These schemata use C<scp> to transfer files. The use of an C<ssh-agent>
+is highly recommended.
+
+=back
+
+
+
 =head1 ENVIRONMENT VARIABLES
 
 For ease in scripting and debugging, C<install-tl> will look for the
@@ -2916,6 +2950,47 @@ user installations.
 
 =over 4
 
+=item C<TEXLIVE_DOWNLOADER>
+
+=item C<TL_DOWNLOAD_PROGRAM>
+
+=item C<TL_DOWNLOAD_ARGS>
+
+These options allow selecting different download programs then the ones
+automatically selected by the installer. The order of selection is:
+
+=over 8
+
+=item 1.
+
+If the environment variable C<TEXLIVE_DOWNLOADER> is
+defined, use it; abort if the specified program doesn't work.
+Possible values: C<curl>, C<wget>.
+
+=item 2.
+
+If the environment variable C<TL_DOWNLOAD_PROGRAM> is
+defined (can be any value), use it together with
+C<TL_DOWNLOAD_ARGS>; abort if it doesn't work.
+
+=item 3.
+
+If LWP is available and working, use that (by far the most
+efficient method, as it supports persistent downloads).
+
+=item 4.
+
+If curl is available (from the system) and working, use that.
+
+=item 5.
+
+If wget is available (either from the system or TL) and working, use that.
+
+=back
+
+TL still provides C<wget> binaries for some platforms, so
+some download method should always be available.
+
 =item C<TEXLIVE_INSTALL_ENV_NOCHECK>
 
 Omit the check for environment variables containing the string C<tex>.