COMTRAN Reconstruction

J28-6169 · January 1962

90.02.04

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[90.02.04]

II. TS - Temporary Storage

Temporary Storage cells are generated by the Compiler to temporarily store an item. The difference between Temporary Storage cells and Result Storage cells is that Temporary Cells are not section-qualified. An example of an instruction referring to Temporary Storages might be:

ANA    TS)1

Temporary Storage cells are reserved immediately after Result Storage cells by the instruction.

TS)    BSS    N

where N is the total number of cells to be reserved.

III. BL - Base Locator

Base Locator cells are a type of 'pointer word'. These pointer words address one of two types of data, namely:

  1. Records located in a buffer.
  2. Data located after a variable length array.

References to Base Locators occur in the symbolic listing whenever the pointer word must be changed. This type of reference to a Base Locator is usually part of a 'GET' calling sequence to the Input/Output system. An example of a sequence that changes the value of a Base Locator due to locating data within an input buffer might be:

TSX      IOC)8,4
PZE      FILENAME,,SYS)260
PZE      END-OF-FILE-PROCEDURE,,ERROR-PROCEDURE
IOCDN*   BL)2,,14

This sequence of instructions fills in the cell BL)2 with the location of the first word of a 14 word record which is in an input buffer.

Following the updating of a Base Locator further references to BL's may occur in the form:

LAC    BL)2,4
CAL    DATANAME,4

References to data located by means of a Base Locator is usually done in this manner, i.e., by first loading an index register with the 2's complement of the location of the first word (the base) of the data block and then referencing any data item within that block by using the relative word position or displacement from the beginning of the block.