$FDef - Revision history

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2018-06-15T18:10:59Z

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	<tr><th>filename</th>		<tr><th>filename</th>
	<td>A %variable or a literal name of the file. A file synonym name can also be used. ~~When~~ <~~var class="term">filename</var~~>=<var class="term">~~groupname~~</var> the <var>$FDef</var> function assumes that the name passed is a file name, not a group name. </td></tr>		<td>A %variable or a literal name of the file. A file synonym name can also be used.
			<p>
			If <var class="term">filename</var> is the name of a group, the <var>$FDef</var> function assumes that the name passed is a file name, not a group name. </p></td></tr>

	<tr><th>location</th>		<tr><th>location</th>

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Mlarocca: Mlarocca moved page $FDEF to $FDef: Lower case change

2014-07-21T17:41:27Z

Mlarocca moved page $FDEF to $FDef: Lower case change

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ELowell at 19:20, 13 August 2013

2013-08-13T19:20:21Z

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	<b>Syntax</b>		<b>Syntax</b>
	<p>The format for the $FDEF function is:</p>		<p>The format for the $FDEF function is:</p>
	<p class="~~code~~">%image:item = $FDEF(<var>[</var>FILE<var>]</var> filename <var>[</var>AT location<var>]</var>, fieldname)		<p class="syntax">%<span class="term">image</span>:<span class="term">item</span> = $FDEF(<var>[</var>FILE<var>]</var> <span class="term">filename</span> <var>[</var>AT <span class="term">location</span><var>]</var>, fieldname)
	</p>		</p>
	<p>where:</p>		<p>where:</p>
	<ul>		<ul>
	<li>%image:item is the image item to which $FDEF returns the data.</li>		<li>%<var class="term">image</var>:<var class="term">item</var> is the image item to which $FDEF returns the data.</li>
	</li>		</li>
	<li>filename is a %variable or a literal name of the file. A file synonym name can also be used. When filename=groupname the $FDEF function assumes that the name passed is a file name, not a group name.</li>		<li><var class="term">filename</var> is a %variable or a literal name of the file. A file synonym name can also be used. When <var class="term">filename</var>=<var class="term">groupname</var> the $FDEF function assumes that the name passed is a file name, not a group name.</li>
	</li>		</li>
	<li>location is the name of the remote node where the file is located.</li>		<li><var class="term">location</var> is the name of the remote node where the file is located.</li>
	</li>		</li>
	<li>fieldname is a %variable or a literal name of the field to be described.</li>		<li><var class="term">fieldname</var> is a %variable or a literal name of the field to be described.</li>
	</li>		</li>
	</ul>		</ul>

Alex: Automatically generated page update

2013-04-20T13:19:01Z

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The $FDEF function lets you access the attributes of a field from within a <var class="product">Model 204</var> procedure. $FDEF maps the attributes of a field, whose values can then be read via an image similar to the ZFIELD image described in [[#$FDEF|$FDEF]]. Unlike $DSCR, which $FDEF supplants, the attributes are displayed in a readable fashion without parsing. $FDEF works only for files (not groups).
Syntax
The format for the $FDEF function is:
%image:item = $FDEF(<var>[</var>FILE<var>]</var> filename <var>[</var>AT location<var>]</var>, fieldname)

where:
<ul>
<li>%image:item is the image item to which $FDEF returns the data.</li>
</li>
<li>filename is a %variable or a literal name of the file. A file synonym name can also be used. When filename=groupname the $FDEF function assumes that the name passed is a file name, not a group name.</li>
</li>
<li>location is the name of the remote node where the file is located.</li>
</li>
<li>fieldname is a %variable or a literal name of the field to be described.</li>
</li>
</ul>
If the field specified in the $FDEF argument is not defined in the opened file specified by filename, $FDEF returns a U (undefined) in the second image item (DEFER.Y_N). If the file is not open, a U is returned in the second (DEFER.Y_N) image item and an N is returned in the third (FRV.Y_N) image item.
FIELD.CODE, which is returned in the 21st image item, is unique for each field within a file. However, this value cannot remain constant for any one field over time, and it cannot be the same for the same field name in different files. Field names do not always hash to the same field codes because of deleted fields and hash collisions. FIELD.CODE, which is returned in the ZFIELD image, is the same as that which appears in CCAJRNL RECTYPE=6 entries. This information is valuable for Technical Support in case you need to run REGENERATE but cannot because you are missing one or more CCAJRNL data sets since your last DUMP of the file.
The ZFIELD image
An image is required by the $FDEF and $LSTFLD functions. The ZFIELD image, which can give you complete field attribute information (see the $FDEF example below), is provided by the <var class="product">Model 204</var> installation software. 
Note: When using ZFIELD, be aware that $FDEF output maps to the image of ZFIELD. Therefore, do not change the order of the image items in ZFIELD.
The location of ZFIELD for your site is listed in this table: 
<table>
<tr class="head">
<th>IF your site runs under...</th>
<th>THEN the ZFIELD image is stored in...</th>
</tr>
<tr>
<td>z/OS</td>
<td>The JCL library</td>
</tr>
<tr>
<td>z/VM</td>
<td>On the 193 MAINT204 disk</td>
</tr>
<tr>
<td>z/VSE</td>
<td>The JCL library</td>
</tr>
</table>
Example
In the example on the next page, you provide a field name and <var class="product">Model 204</var> displays output that indicates if the field is KEY or preallocated. If the field is preallocated, <var class="product">Model 204</var> also displays the number of occurrences and the length of the field. This procedure maps the $FDEF output to the ZFIELD image (shown on the following page). Therefore, if the field is KEY, then the KEY.Y_N image item contains a 'Y'.
PROCEDURE DISPFLD
OPEN DAILY
OPENC VEHICLES
XXXX
BEGIN
%FIELD IS STRING LEN 50
%FIELD = $READ('ENTER FIELDNAME')
* *
* include the ZFIELD proc and prepare the ZFIELD image *
* *
INCLUDE ZFIELD
PREPARE IMAGE ZFIELD
* *
* use the FDEF image item in ZFIELD to check the fieldname *
* *
%ZFIELD:FDEF = $FDEF('VEHICLES',%FIELD)
IF %ZFIELD:KEY.Y_N = 'Y' THEN
PRINT %FIELD ' IS KEY'
ELSE
PRINT %FIELD ' IS NOT A KEY FIELD'
END IF
IF %ZFIELD:OCCURS > '0' THEN
PRINT %FIELD ' IS PREALLOCATED, WITH ' -
%ZFIELD:OCCURS ' VALUES'
PRINT 'THE LENGTH OF ' %FIELD ' IS ' %ZFIELD:LENGTH
ELSE
PRINT %FIELD ' IS NOT PREALLOCATED'
END IF
END

The following is the output produced by the procedure DISPFLD for the field DEDUCTIBLE:
INCLUDE DISPFLD

??ENTER FIELD NAME
DEDUCTIBLE
DEDUCTIBLE IS KEY
DEDUCTIBLE IS PREALLOCATED WITH 1 VALUES
THE LENGTH OF DEDUCTIBLE IS 3

ZFIELD image for $FDEF and $LSTFLD
The following image can be used by the $FDEF and $LSTFLD functions. If you write your own image, be aware that $FDEF maps to the locations of the image items, rather than the names.
IMAGE ZFIELD
NAME IS STRING LEN 255
DEFER.Y_N IS STRING LEN 1
FRV.Y_N IS STRING LEN 1
KEY.Y_N IS STRING LEN 1
MANY.VALUED.Y_N IS STRING LEN 1
CODED.Y_N IS STRING LEN 1
STRING.Y_N IS STRING LEN 1
NUMERIC.RANGE.Y_N IS STRING LEN 1
INVISIBLE.Y_N IS STRING LEN 1
SECURED.Y_N IS STRING LEN 1
UPDATE.IN.PLACE.Y_N IS STRING LEN 1
OCCURS.Y_N IS STRING LEN 1
FLOAT.Y_N IS STRING LEN 1
ORD.NUM.Y_N IS STRING LEN 1
ORD.CHAR.Y_N IS STRING LEN 1
PURE.DBCS.Y_N IS STRING LEN 1
MIXED.DBCS.Y_N IS STRING LEN 1
UNIQUE.Y_N IS STRING LEN 1
OCCURS.ONCE.Y_N IS STRING LEN 1
CLOB.Y_N IS STRING LEN 1
BLOB.Y_N IS STRING LEN 1
FUTURE.EXPANSION IS STRING LEN 34
FIELD.CODE IS BINARY LEN 4 UNSIGNED
ORDERED.Y_N IS STRING LEN 1
LENGTH IS BINARY LEN 1 UNSIGNED
LEVEL IS BINARY LEN 1 UNSIGNED
LRESERVE IS BINARY LEN 1 UNSIGNED
NRESERVE IS BINARY LEN 1 UNSIGNED
SPLITPCT IS BINARY LEN 1 UNSIGNED
NO.OF.IMMEDIATES IS BINARY LEN 1 UNSIGNED
OCCURS IS BINARY LEN 1 UNSIGNED
PAD.CHAR IS STRING LEN 1
FDEF IS STRING LEN 67 AT DEFER.Y_N
BIN1 IS BINARY LEN 4 UNSIGNED
BIN2 IS BINARY LEN 4 UNSIGNED
BIN3 IS BINARY LEN 4 UNSIGNED
BIN4 IS BINARY LEN 4 UNSIGNED
LOOPVAR IS STRING LEN 16 AT BIN1
END IMAGE

[[Category:SOUL $functions]]