☜	Error Code M37 M[UMPS] by Example					☞

M37, READ from device identified by the empty string

Introduced in the 1995 ANSI M[UMPS] language standard.

When the current device is closed, the value of $IO will be set to the empty string. The 1995 ANSI M[UMPS] language standard does not allow read operations to take place while the value of $IO is empty. If, under these circumstances, a Read command is executed, this error will occur.

Note: there is a proposal (March 1995: SC#12 Type B) that would allow read operations from a "null device".

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Copyright © Annotations: 2008-2024 Ed de Moel.

The information in this page is NOT authoritative and subject to be modified at any moment.
Please consult the appropriate (draft) language standard for an authoritative definition.

Some specifications are "approved for inclusion in a future standard". Note that the MUMPS Development Committee cannot guarantee that such future standards will indeed be published.

This page most recently updated on 29-Nov-2011, 22:30:57.

For comments, contact Ed de Moel (demoel@jacquardsystems.com)