103 lines
5.4 KiB
HTML
103 lines
5.4 KiB
HTML
|
<?xml version="1.0" encoding="UTF-8"?>
|
||
|
|
<!DOCTYPE html
|
||
|
|
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
||
|
|
<html lang="en-us" xml:lang="en-us">
|
||
|
|
<head>
|
||
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
||
|
|
<meta name="security" content="public" />
|
||
|
|
<meta name="Robots" content="index,follow" />
|
||
|
|
<meta http-equiv="PICS-Label" content='(PICS-1.1 "http://www.icra.org/ratingsv02.html" l gen true r (cz 1 lz 1 nz 1 oz 1 vz 1) "http://www.rsac.org/ratingsv01.html" l gen true r (n 0 s 0 v 0 l 0) "http://www.classify.org/safesurf/" l gen true r (SS~~000 1))' />
|
||
|
|
<meta name="DC.Type" content="task" />
|
||
|
|
<meta name="DC.Title" content="Decimal length and precision errors" />
|
||
|
|
<meta name="abstract" content="This details errors that occur when a decimal value is passed with incorrect decimal length and precision." />
|
||
|
|
<meta name="description" content="This details errors that occur when a decimal value is passed with incorrect decimal length and precision." />
|
||
|
|
<meta name="DC.subject" content="error, decimal length, precision, decimal length error, precision error" />
|
||
|
|
<meta name="keywords" content="error, decimal length, precision, decimal length error, precision error" />
|
||
|
|
<meta name="DC.Relation" scheme="URI" content="comer.htm" />
|
||
|
|
<meta name="copyright" content="(C) Copyright IBM Corporation 1998, 2006" />
|
||
|
|
<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 1998, 2006" />
|
||
|
|
<meta name="DC.Format" content="XHTML" />
|
||
|
|
<meta name="DC.Identifier" content="dperr" />
|
||
|
|
<meta name="DC.Language" content="en-us" />
|
||
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
||
|
|
<!-- US Government Users Restricted Rights -->
|
||
|
|
<!-- Use, duplication or disclosure restricted by -->
|
||
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
|
||
|
|
<link rel="stylesheet" type="text/css" href="./ic.css" />
|
||
|
|
<title>Decimal length and precision errors</title>
|
||
|
|
</head>
|
||
|
|
<body id="dperr"><a name="dperr"><!-- --></a>
|
||
|
|
<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
|
||
|
|
<h1 class="topictitle1">Decimal length and precision errors</h1>
|
||
|
|
<div><p>This details errors that occur when a decimal value is passed with
|
||
|
|
incorrect decimal length and precision.</p>
|
||
|
|
<div class="section"> <p>If a decimal value is passed with an incorrect decimal length
|
||
|
|
and precision (either too long or too short), a decimal data error (MCH1202)
|
||
|
|
occurs when the variable is referred to. In the following examples, the numeric
|
||
|
|
constant is passed as <samp class="codeph">LEN(15 5)</samp>, but is declared in the called
|
||
|
|
procedure or program as <samp class="codeph">LEN(5 2)</samp>. Numeric constants are
|
||
|
|
always passed as packed decimal <samp class="codeph">(15 5)</samp>. </p>
|
||
|
|
<pre>CALL PGMA PARM(123) /* CALLING PROG */
|
||
|
|
|
||
|
|
PGM PARM(&A) /* PGMA */
|
||
|
|
DCL &A *DEC (5 2)
|
||
|
|
.
|
||
|
|
.
|
||
|
|
.
|
||
|
|
IF (&A *GT 0) THEN(...) /* MCH1202 OCCURS HERE */</pre>
|
||
|
|
<p>If a decimal variable had been declared with <samp class="codeph">LEN(5
|
||
|
|
2)</samp> in the calling program or procedure and the value had been passed
|
||
|
|
as a variable instead of as a constant, no error would occur.</p>
|
||
|
|
<p>If you
|
||
|
|
need to pass a numeric constant to a procedure or program and the procedure
|
||
|
|
or program is expecting a value with a length and precision other than <samp class="codeph">15
|
||
|
|
5</samp>, the constant can be coded in hexadecimal format. The following
|
||
|
|
CALL command shows how to pass the value <samp class="codeph">25.5</samp> to a program
|
||
|
|
variable that is declared as <samp class="codeph">LEN(5 2)</samp>: </p>
|
||
|
|
<pre>CALL PGMA PARM(X'02550F')</pre>
|
||
|
|
<p>If a decimal value is passed with the correct length but with
|
||
|
|
the wrong precision (number of decimal positions), the receiving procedure
|
||
|
|
or program interprets the value incorrectly. In the following example, the
|
||
|
|
numeric constant value (with length (15 5)) passed to the procedure is handled
|
||
|
|
as <samp class="codeph">25124.00</samp>. </p>
|
||
|
|
<pre>CALL PGMA PARM(25.124) /* CALLING PGM */
|
||
|
|
|
||
|
|
PGM PARM(&A) /* PGMA */
|
||
|
|
DCL &A *DEC (15 2) /* LEN SHOULD BE 15 5*/
|
||
|
|
.
|
||
|
|
.
|
||
|
|
.
|
||
|
|
ENDPGM</pre>
|
||
|
|
<p>These errors occur when the variable is first referred to,
|
||
|
|
not when it is passed or declared. In the next example, the called program
|
||
|
|
does not refer to the variable, but instead simply places a value (of the
|
||
|
|
detected wrong length) in the variable returned to the calling program. The
|
||
|
|
error is not detected until the variable is returned to the calling program
|
||
|
|
and first referred to. This kind of error can be especially difficult to
|
||
|
|
detect. </p>
|
||
|
|
<pre>PGM /* PGMA */
|
||
|
|
DCL &A *DEC (7 2)
|
||
|
|
CALL PGMB PARM(&A) /* (7 2) PASSED TO PGMB */
|
||
|
|
IF (&A *NE 0) THEN(...) /* *MCH1202 OCCURS HERE */
|
||
|
|
.
|
||
|
|
.
|
||
|
|
.
|
||
|
|
ENDPGM</pre>
|
||
|
|
<pre>PGM PARM(&A) /* PGMB */
|
||
|
|
DCL &A *DEC (5 2) /* WRONG LENGTH */
|
||
|
|
.
|
||
|
|
.
|
||
|
|
.
|
||
|
|
CHGVAR &A (&B-&C) /* VALUE PLACED in &A */
|
||
|
|
RETURN
|
||
|
|
When control returns to program PGMA and &A is referred to, the error occurs.</pre>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
<div>
|
||
|
|
<div class="familylinks">
|
||
|
|
<div class="parentlink"><strong>Parent topic:</strong> <a href="comer.htm" title="This describes the errors encountered most frequently in passing values on a CALL command or a CALLPRC command. Some of these errors can be very difficult to debug, and some have serious consequences for program functions.">Common errors when calling programs and procedures</a></div>
|
||
|
|
</div>
|
||
|
|
</div>
|
||
|
|
</body>
|
||
|
|
</html>
|