! file update.txt
!      ==========
!
! version 3, 7-Jan-97
!
! Docu for SH-update via FTP
! K. Stammler, 27-Dec-96



SH source code updates are available via ftp.  More recent versions of SH
(versions SH-4.0h and higher)
contain three script files in $SH_UTIL for requesting, transferring and
installing of SH updates.  Before calling these scripts make sure that
you have setup a proper ~/.netrc file for our anonymous ftp server which
enables you to log on without entering your (e-mail)-password
interactively.  You may check this by entering

   ftp ftp.szgrf.uni-erlangen.de

If you are prompted for a password your .netrc is not set up properly
(Terminate ftp with 'bye' after this check).  To configure your .netrc file
create one on your home-directory ($HOME/.netrc) or append to an already
existing one.  The following line must be inserted/appended to a new/existing
.netrc file:

   machine ftp.szgrf.uni-erlangen.de  login ftp  password <your-email-address>

The keyword and parameters are separated by one or more blanks.  The last
expression in the line is your e-mail address which you would have to enter
as password when using anonymous ftp.  If you have created a new .netrc file
change the access mode to 600:

  chmod 600 $HOME/.netrc

After your .netrc file is correctly setup you may call the update-scripts.
Please use a unique filename for your updates since all requests are
processed in the same directory at the SZGRF.  If you are using this ftp-option
the first time contact me (klaus@szgrf.uni-erlangen.de) and ask for a name
to use.  The three shell scripts to use are:


$SH_UTIL/ftp_request_update.csh $SH_ROOT <your-name>.vrs
-------------------------------
This script extracts all version numbers out of the source codes in your
SH-tree and transmits them to the SZGRF server.  This may take 10-20 min.

At the SZGRF server all *.vrs files are processed once a day and compared
with the most recent version.  The *.vrs files are replaced by 'gzip'ped
tar-files with updated source codes if any available.  The update
process at SZGRF runs currently at 22:59 Central European (Summer-)Time
(this is 21:59 GMT in winter and 20:59 GMT in summer).


$SH_UTIL/ftp_get_update.csh <your-name>.tar.gz
---------------------------
After the update-process at SZGRF has processed your <your-name>.vrs file
you transmit with this script the resulting update-file <your-name>.tar.gz
to your computer.


$SH_UTIL/install_ftp_update.csh <your-name>.tar.gz
-------------------------------
This unzips and untars the updated software and compiles it.  It assumes that
the file $SH_ROOT/setup/shsetup is properly configured to compile
SH on your system.  If you are updating an older version of SH, please
check the '$SH_ROOT/setup/shsetup'-file.  This file is not updated
automatically, because it is usually different on every machine.  The
most recent version of the shsetup file at SZGRF is separately available
on '/pub/software/shsetup.sample'.  If you have problems with your
setup use this sample file and change the settings to match your environment.






There are always two pairs of executables in an installation, (SH,SHM) and
(SH_N,SHM_N).  On older versions of SH 'SH_N' has been named 'SHN'.  This
can be changed in the shsetup-file.  The install_ftp_update.csh script only
changes the '*_N' programs.  After an SH-update installation you should use
SH_N or SHM_N in order to run the updated programs.  With SH or SHM you get
the old and unchanged versions.  These backup executables are installed just
in case a new version contains a severe bug or malfunction.  Once you have
tested the new versions and want to use them as backup executables in future
(i.e. copy SH_N,SHM_N to SH,SHM, respectively) enter:

  cd $SH_ROOT
  make world





PLEASE NOTE !
-------------



Be aware that frequent updates of this software also increases the possibility
of creating and using an executable with an undetected severe malfunction or
with manipulations of maleficent system intruders.  Of course, I try to
keep this possibility small, but nobody's perfect.  I won't be responsible
for damage or loss of your files in any case.  So, MAKE BACKUP's !!!



Klaus Stammler
7-Jan-97

