Application compatibility

Compatibility for SCO OpenServer applications on UnixWare is provided by the UnixWare kernel, and the runtime libraries, command executables, and system files provided in standard system directories or in the /OpenServer directories.

Compatibility features for SCO OpenServer applications include the following:

• the custom(1M) installation tool is provided for installing SCO OpenServer packages on UnixWare 7 (note that custom+ and custom+ format package options are not supported)

• the kernel has been modified to detect a special mark in the header section of a binary that identifies it as an SCO OpenServer application; special kernel processing is invoked when this mark is detected; see elfmark(1)

• some UnixWare commands (those that have an SCO OpenServer version in /OpenServer/bin) have been modified to use the SCO OpenServer commands when the OSRCMDS variable is set and exported in the current process's execution environment

Application (or, binary) compatibility was designed to be automatic. The UnixWare 7 kernel recognizes SCO OpenServer applications installed with custom(1M) (as well as pkgadd(1M) installed packages) and can detect applications compiled for use on SCO OpenServer Release 5. As such, you should use the same instructions that were provided with your SCO OpenServer application to install and run your application on UnixWare 7.

Some applications may experience minor problems, due to implementation differences on the two systems. If your SCO OpenServer application does not install or run correctly on UnixWare 7, try one or more of the steps listed below.

General Steps:

Try setting the following switches:

• Enter:

     OSRCMDS=on
  

  before installing or running the application. Setting the OSRCMDS environment variable in the current process environment causes the shell to invoke the OpenServer specific version of some commands that are found in /OpenServer/bin.

• Run the scompat command to change driver (ioctl) settings for applications that run on the system 'console'. See scompat(1).

• Use the elfmark(1) command to add an identifier to SCO OpenServer Extensible Linking Format (ELF) binaries that may not have been detected properly (e.g., applications built using some third party compilers).

Installation failures:

If your application has problems detecting your System Type, System Release, or executing installation and/or shell scripts:

• If failure occurs from an install/shell script, try entering:

     OSRCMDS=on
     export OSRCMDS
  

  in the current process execution environment before installing or running the application. This will force the system to use SCO OpenServer versions of some commands and utilities.

• If the failure is due to a file that is not present on your system, try copying the appropriate file from an SCO OpenServer system. If you do not have an SCO OpenServer system available, see the manual pages for SCO OpenServer at the SCO OpenServer Products web site. and click on the Manuals link. Look in the Reference Documentation Set for a description of the file, and try to re-create the file yourself on your UnixWare 7 system.

Application tuning:

Though uncommon, if the application fails during system "tuning", note which tunables are being set by the application. Try setting the equivalent UnixWare tunable(s) by hand and then installing or running the application again.

Terminal behavior:

If your application is a console or "character-based" application and it doesn't display correctly on your screen:

• First try setting your terminal (TERM variable) to another type. If this doesn't work, try using the SCO OpenServer version of the terminal information file (terminfo) by copying it from an SCO OpenServer system. The files are found under /usr/lib/terminfo in a subdirectory that matches the value of TERM.

• Try setting the poll_delay_compatibility tunable to change what happens for SCO OpenServer binaries that poll with zero timeout.

• Push the ttcompat streams module on all tty-like stacks.