MODPROT parameter: Difference between revisions

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load module protection facility.
load module protection facility.
The load module protection facility protects the reentrant parts of the
The load module protection facility protects the reentrant parts of the
''Model 204'' load module from update after initialization.
<var class="product">Model 204</var> load module from update after initialization.
Since most of ''Model 204'' is reentrant, this facility protects most of the
Since most of <var class="product">Model 204</var> is reentrant, this facility protects most of the
''Model 204'' load module from accidental corruption, thus increasing the
<var class="product">Model 204</var> load module from accidental corruption, thus increasing the
Online's reliability.
Online's reliability.


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<dl>
<dl>
<dt>X'01'
<dt>X'01'
<dd>Protect the reentrant parts of the ''Model 204'' load module.
<dd>Protect the reentrant parts of the <var class="product">Model 204</var> load module.
This bit should always be left on.
This bit should always be left on.
<dt>X'02'
<dt>X'02'
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</dl>
</dl>
The default value for MODPROT is X'01', which means that most of the
The default value for MODPROT is X'01', which means that most of the
''Model 204'' load module is protected, but FUNU and PTCH are not.
<var class="product">Model 204</var> load module is protected, but FUNU and PTCH are not.


Setting MODPROT will not affect *ZAP.
Setting MODPROT will not affect *ZAP.
A *ZAP of a protected part of the ''Model 204'' load module will temporarily
A *ZAP of a protected part of the <var class="product">Model 204</var> load module will temporarily
turn off the module protection for the area being *ZAP'ed.
turn off the module protection for the area being *ZAP'ed.
[[Category:System parameters]]
[[Category:System parameters]]
[[Category:Parameters]]
[[Category:Parameters]]

Revision as of 01:02, 30 October 2012

Summary

Default value
X'01'
Parameter type
System
Where set
User 0 CCAIN parameters
Related products
All
Introduced
Before Sirius Mods 6.7

Description

This User 0 system parameter is a bitmask parameter that controls the load module protection facility. The load module protection facility protects the reentrant parts of the Model 204 load module from update after initialization. Since most of Model 204 is reentrant, this facility protects most of the Model 204 load module from accidental corruption, thus increasing the Online's reliability.

The meaning of the bits in this parameter are:

X'01'
Protect the reentrant parts of the Model 204 load module. This bit should always be left on.
X'02'
Protect FUNU. FUNU contains locally maintained $functions, so it cannot be assumed to be reentrant. However, if FUNU is known to be reentrant, this bit can be set.
X'04'
Protect PTCH. PTCH contains early warning code. While this code is generally reentrant, this is not guaranteed to be the case. Still, it is probably generally safe to set this bit.

The default value for MODPROT is X'01', which means that most of the Model 204 load module is protected, but FUNU and PTCH are not.

Setting MODPROT will not affect *ZAP. A *ZAP of a protected part of the Model 204 load module will temporarily turn off the module protection for the area being *ZAP'ed.