$Context

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Determine if string is name of open file or group

Note: Many $functions have been deprecated in favor of Object Oriented methods. There is no OO equivalent for the $Context function.

$Context allows a user to determine if a string contains the name of an open file or group.

$Context accepts one argument and returns a numeric code.

Syntax

%result = $Context(fgname)

%result A numeric variable that is set to indicate the success of the function:

0 - String does not specify an open file or group 1 - String specifies an open group 2 - String specifies an open file

fgname The name to be tested. This name can be either of these:
  • An unqualified name, in which case the standard Model 204 search order (TEMP GROUP, PERM GROUP, FILE) is used to identify the file or group.
  • A qualified name that explicitly indicates whether $Context is to act on a file or group.

If fgname is not specified, the default file or group at compile time is used.

Some examples of qualified names follow:

'TEMP GROUP FOO' 'FILE HOHO' 'PERM GROUP CHUCKLES' 'GROUP KRUSTY'

Note: The last example is not fully qualified, so $Context first looks for a temporary group, then a permanent group. If the specified entity is a file that is only open as a member of a group, $Context returns a 0 indicating that the file is not open as an individual file.

Examples

  1. In the following example, %rc is set to 1 if file KRUSTY is open:

    %rc = $Context( 'FILE KRUSTY' )

  2. In the following example, %rc is set to 1 if BURNS identifies an open file, 2 if BURNS identifies an open group, and 0 if it identifies neither:

    %rc = $Context( 'BURNS' )

  3. In the following example, %rc is set to 2 if NUKEM is open as a temporary group, and set to 0 otherwise:

    %rc = $Context( 'TEMP GROUP NUKEM' )

Products authorizing $Context