TECHNICAL INFORMATION DOCUMENT TITLE: PTF152 - XENIX File Locking Patch DOCUMENT ID: TID300027 DOCUMENT REVISION: B DATE: 25JAN95 ALERT STATUS: Yellow INFORMATION TYPE: Symptom Solution README FOR: PTF152 PRODUCT and VERSION: UnixWare 1.1 ABSTRACT: The ptf152 file contains the patch which corrects a problem in UnixWare's support of XENIX file locking calls (a feature of the Enhanced Application Compatibliity package). SYMPTOM When using the locking() function call on a file which resides on a NetWare Server, the file locking was not properly accomplished. SOLUTION Apply the ptf152 file. Installation Instructions: DATATYPE: datastream 1. Download the ptf152.Z and ptf152.txt files to the /tmp directory on your machine. 2. Read the release notes contained in this file. 3. Now become root, uncompress the file and add the package to your system using the following commands: $ su # uncompress /tmp/ptf152.Z # pkgadd -d /tmp/ptf152 ptf152 Solution Specifics These release notes acquaint you with the contents of UnixWare PTF152 - XENIX File Locking Patch 1. General Description This patch corrects a problem in UnixWare's support of XENIX file locking calls (a feature of the Enhanced Application Compatibliity package). The effect of the problem was that multiple processes were allowed to concurrently hold an exclusive lock on the same region of a file. After installing this patch, XENIX file locking calls will now function correctly; the second and subsequent processes requesting a lock on a region of a file will be suspended until the process that is holding an exclusive lock on that region has released the lock. 2. New Features None 3. Software Notes and Recommendations This patch should be installed on all UnixWare 1.1.1 systems which have the Enhanced Application Compatibility package installed and are using applications which use XENIX file locking calls. It may be installed, if desired, on systems without the Enhanced Application Compatibility package, in the event Enhanced Application Compatibility is installed in the future. This patch requires UnixWare 1.1.1 (UnixWare 1.1.1 is 1.1 with Update 5 installed) to be installed on the system. This patch is intended for UnixWare 1.1.1 systems only and cannot be installed on other systems. 4. Hardware Notes and Recommendations None 5. Installation Instructions Depending on the format: If this PTF was delivered on a diskette, then (as "root") pkgadd -d diskette1 should install this patch. Otherwise, if you have a file such as "ptf152" which is in a "stream" format, then (as "root") pkgadd -d /ptf152 will work. After installing this patch, a system reboot will be need to rebuild the kernel and incorporate the updated drivers. 6. Troubleshooting Confirming that XENIX file locking calls function correctly after this patch is installed will require the use of a user-developed test program. The program should lock a specific region of a file and display a message when it has successfully done so. Before this patch is installed, when the program is executed multiple time concurrently, it will be observed that multiple processes have concurrently locked the same file region. After installing this patch, it will be observed that the second and subsequent processes are suspended until the first process has released the lock.