Technical data
System Dump Analyzer
SHOW EXECUTIVE
SHOW EXECUTIVE
Displays the location and size of each loadable image that makes up the
executive.
Format
SHOW EXECUTIVE
Parameters
None.
Qualifiers
None.
Description
The executive consists of a fixed portion and a loadable portion. The fixed portion
is known as SYS$SYSTEM:SYS.EXE and consists of three parts:
• System service dispatch vectors
• Universal executive routine vectors
• Globally referenced data cells
The loadable portion consists of a number of independent images that perform
the work of the operating system.
The SHOW EXECUTIVE command lists the location and size of each image
within the loadable portion of the executive image. It can thus enable you to
determine whether a given memory address falls within the range occupied by a
particular loadable image. (Table SDA–13 describes the contents of each loadable
image.)
By default, SDA displays each location within the loadable portion of the
executive as an offset from the beginning of one of the loadable images; for
instance, EXCEPTION+00282. Similarly, those symbols that represent system
services point to the vector region and not to the system service’s loadable code.
When tracing the course of a system failure through the listings of modules
contained within a given loadable executive image, you might find it useful to
load into the SDA symbol table all global symbols and global entry points defined
within one or all modules that make up the loadable portion of the executive
image. See the description of the READ command for additional information.
The SHOW EXECUTIVE command usually shows all components of the executive
image, as illustrated in the following example. In rare circumstances, you might
obtain a partial listing. For instance, once it has loaded the EXCEPTION module
(in the INIT phase of system initialization), the system can successfully post
a bugcheck exception and save a crash dump. Later, if the system should fail
sometime during initialization, it might not have been able to load some of the
modules that appear above EXCEPTION in the SHOW EXECUTIVE display (see
the example).
SDA–110