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$IOREFERENCE

Draft MDC Standard

7.1.4.10.7 $IOReference

$IOR[EFERENCE]

identifies the current I/O device (see 8.2.7 and 8.2.35). Its value has the syntax of devn with the following restrictions:

  1. When a process is initiated, but before any commands are processed, the value of $IOReference is equal to the value of $Principal if an implicit Open and Use for the device specified by $Principal is executed by the implementation. If the implementation does not execute these Open and Use commands then $IOReference is given the value of the empty string.
  2. If the last command that changed $IOReference included an environment, then the value returned by $IOReference shall include that environment; otherwise the value of $IOReference shall not include an environment.
  3. An environment whose value has the form of a number as defined in 7.1.4.3 appears as a numlit, spelled as its numeric interpretation.
  4. An environment whose value does not have the form of a number as defined in 7.1.4.3 appears as a strlit.
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Copyright © Standard Documents; 1977-2024 MUMPS Development Committee;
Copyright © Examples: 1995-2024 Ed de Moel;
Copyright © Annotations: 2003-2008 Jacquard Systems Research
Copyright © Annotations: 2008-2024 Ed de Moel.

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This page most recently updated on 28-Nov-2011, 21:03:45.

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