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CALL
CALL
The CALL; command enables access to external routines or programs. For each target host
type, you can use a CALL; command to access:
$ MCP based Library procedures, by title or by System Library (SL) function name
For MCP based LINC Systems, the CALL; BYFUNCTION variant gives you access to
common user libraries that have been installed using the SL system command. For
more details, see the following subsection ‘‘Using BYFUNCTION; with the CALL;
Command’’.
$ MCP based LINC Reports as Coroutines.
$ OS 2200 based COBOL or Assembler programs or procedures, and LINC Subroutine
Reports (in conjunction with the LINCSUB SGS)
$ UNIX programs or routines, or the shell
For UNIX LINC Systems, external COBOL programs exist as programs separate from
the LINC System. Their location is contained in the environment variable COBPATH.
$ Dynamic Linc Libraries (DLL)
In LDA, the entry points used with the CALL: command to access DLLs are case
sensitive.
$ LDA Reports that have been specified as Able to be run as a Sub/Coroutine
Parameter Passing
Parameters can be passed by using the System Data item GLB.PARAM, whose value you
must define before executing the CALL; command. Data returned from the routine also
uses GLB.PARAM.
Note: The internal common field used to pass this information is GLBPARAM (not
GLB-PARAM), which enables access by programs written in a variety of
languages.
For information on passing parameters when using internal or external routines with the
CALL; command, see your UNIX LINC Administration and Operations Guide.
Checking of Operands
No syntax checking is performed on the literal operands of the CALL; command. It is your
responsibility to ensure that the literal operand conforms to the syntax requirements of the
compiler you are using to generate the runtime system. If not, your generate will fail. It is
also your responsibility to ensure the library procedure, routine, or program being called
actually exists, and is able to be called at runtime. If not, the calling LINC System or Report
will abort.
For More Information
For more details, see:
$
"Syntax" for each host type, later in this subsection
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