Chapter 7: Fileshare on UNIX

UNIX:
This chapter describes Fileshare on UNIX.

7.1 Running Fileshare as a Background Process

Because the Fileshare Server uses Adis for its screen displays and keyboard handling, it accumulates a lot of processor time if started as a background process on UNIX. To avoid this, and allow the Fileshare Server to only use its usual amount of processor time while in the background, the Fileshare Server should be configured using the -b option when being run in the background. This disables all Fileshare displays and keyboard reading.

Since Fileshare does not read the keyboard in background mode, you cannot close it down in the normal manner using the ESC key sequence.

Warning: Do not kill the Fileshare process because this will result in the corruption of any data files which are open.

Instead, write a program which calls Fileshare Manager (FSMgr). Alternatively, you can run the supplied utility fsclose as follows:

cobrun fsclose

The fsclose utility calls Fileshare Manager itself and prompts you for the name of the Fileshare Server you want to close down and the CCI protocol.

Because the only way to shut down the Fileshare Server is remotely, the Fileshare Server must have been configured to use a password file. See the section Password File Maintenance in the chapter Security for details.

The Fileshare Server does not start in background mode unless you start it with a password file.

In background mode, any messages the Fileshare Server would normally display on the screen are written to the file fsscreen.lst in the Fileshare Server's current directory.

An example configuration file follows. This configuration file specifies that the Fileshare Server name is server-1, the password file is password.fil and the communications protocol to use is CCITCP. The -b option specifies background mode.

-s server-1
-pf password.fil
-b
-cm ccitcp

The Fileshare Server can now be started in background mode by entering:

fs > server-1.log 2>&1

You need to redirect the output from the command because otherwise, on some UNIX systems, output is sent to the terminal after it has been disconnected and, consequently, the entire session is terminated.

7.2 The NFILES Setting

On UNIX systems, the NFILES setting defines how many separate file descriptors can be used. This can be set for individual accounts and for the system as a whole. You must ensure that NFILES is set sufficiently high for Fileshare which uses file descriptors as follows:

One file descriptor is used for every file opened on disk. So, two file descriptors are used for each indexed file opened. Note that two users sharing the same file only require the file to be opened once on disk.
CCITCP uses one file descriptor for every connected Fileshare client.
CCITCP uses one file descriptor for every outstanding Fileshare request (normally this is a maximum of two).

So, for the user account that the Fileshare session uses, NFILES must be set to accomodate the maximum number of open files and the maximum number of Fileshare clients. In addition, the system setting of NFILES may need to be increased.