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Class: ExternalInt


Inheritance:

   Object
   |
   +--Collection
      |
      +--SequenceableCollection
         |
         +--ArrayedCollection
            |
            +--UninterpretedBytes
               |
               +--ExternalBytes
                  |
                  +--ExternalInt

Package:
stx:libbasic2
Category:
System-Support
Version:
rev: 1.1 date: 2018/02/05 17:35:22
user: cg
file: ExternalInt.st directory: libbasic2
module: stx stc-classLibrary: libbasic2

Description:


Instances of me can be used as container in which int values are returned from C-calls. 
Notice that the size of these ints depends on the machine's (and compiler's) int-size
(which is ExternalBytes sizeofInt).


Class protocol:

instance creation
o  new
allocate some memory usable to hold a C-int;
the memory is not controlled by the garbage collector.
Return a corresponding ExternalBytes object or raise MallocFailure (if malloc fails).

Use this, if you have to pass a pointer to an integer
external destination (such as a C function) which does not copy the
data, but instead keeps a reference to it.

DANGER ALERT: the memory is NOT automatically freed until it is either
MANUALLY freed (see #free) or the returned externalBytes object
is unprotected or the classes releaseAllMemory method is called.
usage example(s):
     ExternalInt new

o  unprotectedNew
allocate some memory usable to hold a naitve C-int;
the memory is under the control of the garbage collector.
Return a corresponding ExternalBytes object or raise MallocFailure (if malloc fails).

DANGER ALERT: the memory block as allocated will be automatically freed
as soon as the reference to the returned externalBytes object
is gone (by the next garbage collect).
If the memory has been passed to a C-function which
remembers this pointer, bad things may happen ....


Instance protocol:

accessing
o  asExternalBytes
(ExternalLong new value:10) asExternalBytes
(ExternalLong new value:0) asExternalBytes

o  asInteger
warning: retrieves a signed integer with the size of the native machine's
pointer (i.e. either 32 or 64bit)
usage example(s):
     ExternalInt new value:10
     (ExternalInt new value:16rFFFFFF) asInteger

o  asUnsignedInteger
warning: retrieves an integer with the size of the native machine's
pointer (i.e. either 32 or 64bit)
usage example(s):
     (ExternalInt new value:10) asUnsignedInteger

o  value
(ExternalInt new value:10) value

o  value: anInteger
(ExternalInt new value:10) value

printing & storing
o  printOn: aStream



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