Browse Prior Art Database

Sigterm Signal Handler for the OS/2 Database Manager

IP.com Disclosure Number: IPCOM000122610D
Original Publication Date: 1991-Dec-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Jacobs, DC: AUTHOR

Abstract

A method is described which will insure that the OS/2* Database Manager (DBM) is in a safe state when a program terminate signal is generated by an application using the DBM. Background

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This is the abbreviated version, containing approximately 52% of the total text.

Sigterm Signal Handler for the OS/2 Database Manager

      A method is described which will insure that the OS/2*
Database Manager (DBM) is in a safe state when a program terminate
signal is generated by an application using the DBM.
Background

      The OS/2 operating system supports the use of signals as a form
of interprocess communication.  There are certain system default
effects which occur when these signals are generated.  The OS/2
termination signal SIGTERM is used to bring down a process and its
children.  This signal is generated with the DOSKILLPROCESS or
DOSEXIT OS/2 function call or when a ICON is "closed" from the main
desk top.  The default effects of the signal is that all file buffers
are flushed and the handles opened by  the process are closed.
Internal buffer managed by programs outside of OS/2 will not be
flushed.
Problem

      The accuracy of the data which is stored in a relational
database is imperative.  If data is missing as a result of some
unforeseen disaster or side  effect, then the accuracy of data stored
in the database is compromised; relations will be invalid.

      An example of one of these disasters could occur as a result of
an application generating a SIGTERM signal by issuing a
DOSKILLPROCESS or DOSEXIT.  Issuing a DOSKILLPROCESS or DOSEXIT is
not an uncommon practice in error conditions.  It is essential that
the OS/2 Database Manager be protected in the event that a SIGTERM
signal is generated.  If the default effect of the SIGTER...