任何人都可以提供这些有趣的使用示例吗？
问问题
2393 次
4 回答
4
举一个实际的例子，这可以在实现回调时使用。可以在 C 中的 qsort() 函数中找到一个常见的回调。是的，您可以从 ILERPG 中调用它。
qsort()的C规范是：
#include <stdlib.h>
void qsort(void *base, size_t num, size_t width,
int(*compare)(const void *key, const void *element));
RPGLE原型看起来像：
dcl-pr qsort ExtName('qsort');
array Pointer value;
num Uns(10) value;
width Uns(10) value;
compare Pointer(*proc) value;
end-pr;
这是一个使用 qsort() 的简单程序：
ctl-opt DftActGrp(*No) Actgrp(*New);
dcl-pr qsort ExtProc('qsort');
array Pointer value;
num Uns(10) value;
width Uns(10) value;
compare Pointer(*Proc) value;
end-pr;
dcl-s strings Varchar(10) Dim(20);
strings(1) = 'Does';
strings(2) = 'this';
strings(3) = 'array';
strings(4) = 'sort';
strings(5) = 'properly?';
qsort(%addr(strings): 5: %size(strings): %paddr(compareStrings));
dsply strings(1);
dsply strings(2);
dsply strings(3);
dsply strings(4);
dsply strings(5);
return;
dcl-proc compareStrings;
dcl-pi *n Int(10);
key Like(strings);
element Like(strings);
end-pi;
dcl-s result Int(10);
if key < element;
result = -1;
elseif key = element;
result = 0;
else;
result = 1;
endif;
return result;
end-proc;
如果你运行它，输出将是：
DSPLY array
DSPLY properly?
DSPLY sort
DSPLY this
DSPLY Does
于 2017-04-28T13:06:02.620 回答
2
朱朱马，
对于一个简单的示例，您可以使用它来实现一些面向对象的样式过程，例如 Draw。通过将 Circle_Draw 或 Square_Draw 的适当 %PADDR 分配给 Draw 过程指针，您可以为 Circle 调用 Circle_Draw 过程或为 Square 调用 Square_Draw 过程。当调用 Draw 过程指针时，您隐藏了正在调用的过程（Circle_Draw 或 Square_Draw）。
于 2009-04-28T20:25:35.090 回答
2
我已经使用过程指针将搜索假脱机文件的逻辑封装到它自己的名为SPLFFUNCfor 的服务程序中，以便更容易地对其进行迭代。
在调用程序中，您可以使用如下代码：
ForEachSPLF(%paddr(ProcessSPLA0100) :
'SPLA0100' : // desired format, can be SPLF0100, SPLF0300, or SPLA0100
*BLANKS : // filter for all user names
ToUpper(SendQueue) : // out queue
ToUpper(SendQueueLib) : // out queue library
*BLANKS : // filter for all form types
*BLANKS ); // filter for any user data
和
P ProcessSPLA0100...
P B
D PI
D SPLA LIKEDS(SPLA0100)
P E
对于每个匹配请求标准的假脱机文件，将调用一次指向的过程。这使您可以返回惰性可枚举而不是数组。我喜欢这个，因为它是可重用的，它不受特定大小的数组的限制（因为我不知道要分配多少），而且它的内存占用要小得多，因为你一次只存储一个数据结构。这大致相当于您在 C# 等语言中使用 lambda 所做的事情。由于指向的过程可以访问客户端程序中的任何全局变量，它关闭它们以执行客户端程序的实际工作。
服务程序中的代码处理调用 API、读取用户空间对象等所有血腥细节。因此可以将这些细节排除在客户端程序之外。
请注意，RPG 不为这种技术提供编译类型类型检查，因此您必须确保您请求的格式和指向过程中定义的数据结构匹配。
服务计划：
H NOMAIN
H DEBUG(*YES)
H THREAD(*SERIALIZE)
H BNDDIR('ERRFUNC')
H OPTION(*SrcStmt:*NoDebugIO)
H TEXT('Services for looping through spooled files')
* To compile:
*
* CRTRPGMOD MODULE(QGPL/SPLFFUNC) SRCFILE(QGPL/QRPGLESRC)
*
* CRTSRVPGM SRVPGM(QGPL/SPLFFUNC) EXPORT(*SRCFILE)
/copy QRPGLESRC,SPLFFUNCPR
/copy QRPGLESRC,ERRFUNCPR
********************************************************************
P ForEachSPLF B EXPORT
D PI
D ExecProcedure * VALUE PROCPTR
D Format 10A VALUE
D UserName 10A VALUE
D OutQueue 10A VALUE
D OutQueueLib 10A VALUE
D FormType 10A VALUE
D UserData 10A VALUE
D CrtUserSpace PR EXTPGM('QUSCRTUS')
D 20A CONST Name
D 10A CONST Attribute
D 10I 0 CONST Intial size
D 1A CONST Initial value
D 10A CONST Authority
D 50A CONST Text
D 10A CONST OPTIONS(*nopass) Replace existing
D 32767A OPTIONS(*varsize:*nopass) Error feedback
D GetPointer PR EXTPGM('QUSPTRUS')
D 20A CONST User space name
D * Pointer
D 32767A OPTIONS(*varsize:*nopass) Error feedback
D DltUserSpace PR EXTPGM('QUSDLTUS')
D QUSPTRUS 20A CONST User space name
D 32767A OPTIONS(*varsize:*nopass) Error feedback
/copy qsysinc/qrpglesrc,qusec
D ListSplFiles PR EXTPGM('QUSLSPL')
D 20A CONST userspace library
D 8A CONST format
D 10A CONST user name
D 20A CONST output queue
D 10A CONST form type
D 10A CONST user data
D 32767A OPTIONS(*varsize:*nopass)
D GetSplfAttrib PR EXTPGM('QUSRSPLA')
D receiver LIKEDS(SPLA0100) receiver structure
D 10I 0 CONST receiver length
D 8A CONST format
D 26A CONST qualified job name
D 16A CONST internal job ID
D 16A CONST internal SPLF ID
D 10A CONST file name
D 10I 0 CONST file number
D 32767A OPTIONS(*varsize:*nopass)
* Generic header format 0100
D GenericHeader DS BASED(UserSpacePointer) QUALIFIED
D ListOffset 10I 0 OVERLAY(GenericHeader:125)
D ListCount 10I 0 OVERLAY(GenericHeader:133)
D ListEachSize 10I 0 OVERLAY(GenericHeader:137)
D SPLF1 DS LIKEDS(SPLF0100) BASED(FieldPointer)
D SPLF3 DS LIKEDS(SPLF0300) BASED(FieldPointer)
D SPLA1 DS LIKEDS(SPLA0100)
D I S 5I 0
D SpaceName S 20A
D FileNum S 10I 0 INZ(0)
D reqFormat S 10A
D ptrSPLF0100 S * PROCPTR
D procSPLF0100 PR EXTPROC(ptrSPLF0100)
D SPLF LIKEDS(SPLF0100)
D ptrSPLF0300 S * PROCPTR
D procSPLF0300 PR EXTPROC(ptrSPLF0300)
D SPLF LIKEDS(SPLF0300)
D ptrSPLA0100 S * PROCPTR
D procSPLA0100 PR EXTPROC(ptrSPLA0100)
D SPLF LIKEDS(SPLA0100)
* Validate Parameters
ptrSPLF0100 = ExecProcedure;
ptrSPLF0300 = ExecProcedure;
ptrSPLA0100 = ExecProcedure;
IF Format <> 'SPLF0100' AND Format <> 'SPLF0300' AND
Format <> 'SPLA0100';
ThrowError('Spooled file information format must be -
''SPLF0100'', ''SPLF0300'', or ''SPLA0100''.');
ENDIF;
IF OutQueue = *BLANKS;
OutQueue = '*ALL';
OutQueueLib = *BLANKS;
ELSE;
IF OutQueueLib = *BLANKS;
OutQueueLib = '*LIBL';
ENDIF;
ENDIF;
IF UserName = *BLANKS;
UserName = '*ALL';
ENDIF;
IF FormType = *BLANKS;
FormType = '*ALL';
ENDIF;
IF UserData = *BLANKS;
UserData = '*ALL';
ENDIF;
* To view this user space object:
*
* DSPF STMF('/QSYS.lib/QTEMP.lib/@SPOOLSPC.usrspc')
* or
* DMPOBJ OBJ(QTEMP/@SPOOLSPC) OBJTYPE(*USRSPC)
SpaceName = '@SPOOLSPC QTEMP';
CrtUserSpace(SpaceName : '' : 131072 : x'00' :
'*ALL':'List of spooled files':'*YES':QUSEC);
* DSPLY ('ListSplFiles' + SpaceName + Format + UserName);
* DSPLY (OutQueue + OutQueueLib + FormType + UserData);
IF Format = 'SPLF0300';
reqFormat = Format;
ELSE;
reqFormat = 'SPLF0100';
ENDIF;
ListSplFiles(SpaceName : reqFormat : UserName :
OutQueue + OutQueueLib : FormType : UserData : QUSEC);
GetPointer(SpaceName : UserSpacePointer) ;
FOR I = 1 to GenericHeader.ListCount ;
FieldPointer = UserSpacePointer
+ GenericHeader.ListOffset
+ (GenericHeader.ListEachSize * (I - 1)) ;
IF Format = 'SPLF0100';
procSPLF0100(SPLF1);
ELSEIF Format = 'SPLF0300';
procSPLF0300(SPLF3);
ELSEIF Format = 'SPLA0100';
GetSplfAttrib(SPLA1 : %size(SPLA1) : 'SPLA0100' : '*INT' :
SPLF1.InternalJobID : SPLF1.InternalSplID :
'*INT' : FileNum : QUSEC);
procSPLA0100(SPLA1);
ENDIF;
ENDFOR;
DltUserSpace(SpaceName : QUSEC) ;
RETURN;
P E
服务程序原型：
D ForEachSPLF PR EXTPROC('ForEachSPLF')
D ExecProcedure * VALUE PROCPTR
D Format 10A VALUE
D UserName 10A VALUE
D OutQueue 10A VALUE
D OutQueueLib 10A VALUE
D FormType 10A VALUE
D UserData 10A VALUE
********************************************************************
D SPLF0100 DS TEMPLATE QUALIFIED INZ
D UserName 10A OVERLAY(SPLF0100:1)
D OutQName 10A OVERLAY(SPLF0100:11)
D OutQLibrary 10A OVERLAY(SPLF0100:21)
D FormType 10A OVERLAY(SPLF0100:31)
D UserSpecData 10A OVERLAY(SPLF0100:41)
D InternalJobID 16A OVERLAY(SPLF0100:51)
D InternalSplID 16A OVERLAY(SPLF0100:67)
D Reserved 2A OVERLAY(SPLF0100:83)
D AuxStorage 10I 0 OVERLAY(SPLF0100:85)
********************************************************************
D SPLF0300 DS TEMPLATE QUALIFIED INZ
D JobName 10A OVERLAY(SPLF0300:1)
D UserName 10A OVERLAY(SPLF0300:11)
D JobNumber 6A OVERLAY(SPLF0300:21)
D FileName 10A OVERLAY(SPLF0300:27)
D FileNumber 9B 0 OVERLAY(SPLF0300:37)
D FileStatus 9B 0 OVERLAY(SPLF0300:41)
D DateCreated 7A OVERLAY(SPLF0300:45)
D TimeCreated 6A OVERLAY(SPLF0300:52)
D Schedule 1A OVERLAY(SPLF0300:58)
D FileSysName 10A OVERLAY(SPLF0300:59)
D UserData 10A OVERLAY(SPLF0300:69)
D FormType 10A OVERLAY(SPLF0300:79)
D OutQName 10A OVERLAY(SPLF0300:89)
D OutQLibrary 10A OVERLAY(SPLF0300:99)
D AuxStorePool 9B 0 OVERLAY(SPLF0300:109)
D Size 9B 0 OVERLAY(SPLF0300:113)
D SizeMult 9B 0 OVERLAY(SPLF0300:117)
D Pages 9B 0 OVERLAY(SPLF0300:121)
D CopiesLeft 9B 0 OVERLAY(SPLF0300:125)
D Priority 1A OVERLAY(SPLF0300:129)
D Reserved 3A OVERLAY(SPLF0300:130)
D InterPrintID 9B 0 OVERLAY(SPLF0300:133)
********************************************************************
D SPLA0100 DS TEMPLATE QUALIFIED INZ
D BytesReturned 10I 0 OVERLAY(SPLA0100:1)
D BytesAvail 10I 0 OVERLAY(SPLA0100:5)
D InternalJobID 16A OVERLAY(SPLA0100:9)
D InternalSplID 16A OVERLAY(SPLA0100:25)
D JobName 10A OVERLAY(SPLA0100:41)
D UserName 10A OVERLAY(SPLA0100:51)
D JobNumber 6A OVERLAY(SPLA0100:61)
D FileName 10A OVERLAY(SPLA0100:67)
D FileNumber 10I 0 OVERLAY(SPLA0100:77)
D FormType 10A OVERLAY(SPLA0100:81)
D UserData 10A OVERLAY(SPLA0100:91)
D Status 10A OVERLAY(SPLA0100:101)
D FileAvailable 10A OVERLAY(SPLA0100:111)
D HoldBefore 10A OVERLAY(SPLA0100:121)
D SaveAfter 10A OVERLAY(SPLA0100:131)
D TotalPages 10I 0 OVERLAY(SPLA0100:141)
D PageWritten 10I 0 OVERLAY(SPLA0100:145)
D StartingPage 10I 0 OVERLAY(SPLA0100:149)
D EndingPage 10I 0 OVERLAY(SPLA0100:153)
D LastPagePrint 10I 0 OVERLAY(SPLA0100:157)
D Restart 10I 0 OVERLAY(SPLA0100:161)
D TotalCopies 10I 0 OVERLAY(SPLA0100:165)
D CopiesLeft 10I 0 OVERLAY(SPLA0100:169)
D LinesPerInch 10I 0 OVERLAY(SPLA0100:173)
D CharsPerInch 10I 0 OVERLAY(SPLA0100:177)
D OutPriority 2A OVERLAY(SPLA0100:181)
D OutQueueName 10A OVERLAY(SPLA0100:183)
D OutQueueLib 10A OVERLAY(SPLA0100:193)
D DateCreated 7A OVERLAY(SPLA0100:203)
D TimeCreated 6A OVERLAY(SPLA0100:210)
D DeviceFileName...
D 10A OVERLAY(SPLA0100:216)
D DeviceFileLib 10A OVERLAY(SPLA0100:226)
D ProgramName 10A OVERLAY(SPLA0100:236)
D ProgramLib 10A OVERLAY(SPLA0100:246)
D AccountingCde 15A OVERLAY(SPLA0100:256)
D PrintText 30A OVERLAY(SPLA0100:271)
D RecordLength 10I 0 OVERLAY(SPLA0100:301)
D MaxRecords 10I 0 OVERLAY(SPLA0100:305)
D DeviceType 10A OVERLAY(SPLA0100:309)
D PrinterType 10A OVERLAY(SPLA0100:319)
D DocumentName 12A OVERLAY(SPLA0100:329)
D FolderName 64A OVERLAY(SPLA0100:341)
D Sys36ProcName 8A OVERLAY(SPLA0100:405)
D PrintFidelity 10A OVERLAY(SPLA0100:413)
D ReplaceUnprintable...
D 1A OVERLAY(SPLA0100:423)
D ReplacementChar...
D 1A OVERLAY(SPLA0100:424)
D PageLength 10I 0 OVERLAY(SPLA0100:425)
D PageWidth 10I 0 OVERLAY(SPLA0100:429)
D NumSeparators 10I 0 OVERLAY(SPLA0100:433)
D OverflowLine 10I 0 OVERLAY(SPLA0100:437)
D MultiByteData 10A OVERLAY(SPLA0100:441)
D DBCSExtenChar 10A OVERLAY(SPLA0100:451)
D DBCSShiftOut 10A OVERLAY(SPLA0100:461)
D DBCSCharRot 10A OVERLAY(SPLA0100:471)
D DBCSCPI 10I 0 OVERLAY(SPLA0100:481)
D GraphCharSet 10A OVERLAY(SPLA0100:485)
D CodePage 10A OVERLAY(SPLA0100:495)
D FormDefName 10A OVERLAY(SPLA0100:505)
D FormDefLib 10A OVERLAY(SPLA0100:515)
D SourceDrawer 10I 0 OVERLAY(SPLA0100:525)
D PrinterFont 10A OVERLAY(SPLA0100:529)
D Sys36SPLFID 6A OVERLAY(SPLA0100:539)
D PageRotation 10I 0 OVERLAY(SPLA0100:545)
D Justification 10I 0 OVERLAY(SPLA0100:549)
D PrintDuplex 10A OVERLAY(SPLA0100:553)
D FoldRecords 10A OVERLAY(SPLA0100:563)
D ControlChar 10A OVERLAY(SPLA0100:573)
D AlignForms 10A OVERLAY(SPLA0100:583)
D PrintQuality 10A OVERLAY(SPLA0100:593)
D FormFeed 10A OVERLAY(SPLA0100:603)
D VolumesArray 71A OVERLAY(SPLA0100:613)
D FileLabelID 17A OVERLAY(SPLA0100:684)
D ExchangeType 10A OVERLAY(SPLA0100:701)
D CharacterCode 10A OVERLAY(SPLA0100:711)
D TotalRecords 10I 0 OVERLAY(SPLA0100:721)
D PagesPerSide 10I 0 OVERLAY(SPLA0100:725)
D FrontOvlName 10A OVERLAY(SPLA0100:729)
D FrontOvlLib 10A OVERLAY(SPLA0100:739)
D FrontOvlOffsetDown...
D 15P 5 OVERLAY(SPLA0100:749)
D FrontOvlOffsetAcross...
D 15P 5 OVERLAY(SPLA0100:757)
D BackOvlName 10A OVERLAY(SPLA0100:765)
D BackOvlLib 10A OVERLAY(SPLA0100:775)
D BackOvlOffsetDown...
D 15P 5 OVERLAY(SPLA0100:785)
D BackOvlOffsetAcross...
D 15P 5 OVERLAY(SPLA0100:793)
D UnitOfMeasure 10A OVERLAY(SPLA0100:801)
D PageDefName 10A OVERLAY(SPLA0100:811)
D PageDefLib 10A OVERLAY(SPLA0100:821)
D LineSpacing 10A OVERLAY(SPLA0100:831)
D PointSize 15P 5 OVERLAY(SPLA0100:841)
D FrontMarginOffsetDown...
D 15P 5 OVERLAY(SPLA0100:849)
D FrontMarginOffsetAcross...
D 15P 5 OVERLAY(SPLA0100:857)
D BackMarginOffsetDown...
D 15P 5 OVERLAY(SPLA0100:865)
D BackMarginOffsetAcross...
D 15P 5 OVERLAY(SPLA0100:873)
D LengthOfPage 15P 5 OVERLAY(SPLA0100:881)
D WidthOfPage 15P 5 OVERLAY(SPLA0100:889)
D MeasurementMethod...
D 10A OVERLAY(SPLA0100:897)
D AFPResource 1A OVERLAY(SPLA0100:907)
D CharSetName 10A OVERLAY(SPLA0100:908)
D CharSetLib 10A OVERLAY(SPLA0100:918)
D CodePageName 10A OVERLAY(SPLA0100:928)
D CodePageLib 10A OVERLAY(SPLA0100:938)
D CodedFontName 10A OVERLAY(SPLA0100:948)
D CodedFontLib 10A OVERLAY(SPLA0100:958)
D DBCSFontName 10A OVERLAY(SPLA0100:968)
D DBCSFontLib 10A OVERLAY(SPLA0100:978)
D UserDefFile 10A OVERLAY(SPLA0100:988)
D ReduceOutput 10A OVERLAY(SPLA0100:998)
D ConstBackOvl 1A OVERLAY(SPLA0100:1008)
D OutputBin 10I 0 OVERLAY(SPLA0100:1009)
D CCSID 10I 0 OVERLAY(SPLA0100:1013)
D UserDefText 100A OVERLAY(SPLA0100:1017)
D CreatedSystem 8A OVERLAY(SPLA0100:1117)
D CreatedID 8A OVERLAY(SPLA0100:1125)
D CreatedUser 10A OVERLAY(SPLA0100:1133)
D 2A OVERLAY(SPLA0100:1143)
D OffsetUserDef 10I 0 OVERLAY(SPLA0100:1145)
D NumberUserDef 10I 0 OVERLAY(SPLA0100:1149)
D LengthUserDef 10I 0 OVERLAY(SPLA0100:1153)
D UsrDefData 255A OVERLAY(SPLA0100:1157)
D UsrDefObjName 10A OVERLAY(SPLA0100:1412)
D UsrDefObjLib 10A OVERLAY(SPLA0100:1422)
D UsrObjType 10A OVERLAY(SPLA0100:1432)
D 3A OVERLAY(SPLA0100:1442)
D CharSetPtSz 15P 5 OVERLAY(SPLA0100:1445)
D CodedFontPtSz 15P 5 OVERLAY(SPLA0100:1453)
D DBCSFontPtSz 15P 5 OVERLAY(SPLA0100:1461)
D AuxStorPool 10I 0 OVERLAY(SPLA0100:1469)
D SPLFSize 10I 0 OVERLAY(SPLA0100:1473)
D SPLFSizeMult 10I 0 OVERLAY(SPLA0100:1477)
D IPJobID 10I 0 OVERLAY(SPLA0100:1481)
D SPLFSecurity 1A OVERLAY(SPLA0100:1485)
D SPLFAuthent 1A OVERLAY(SPLA0100:1486)
D WriterDateBeg 7A OVERLAY(SPLA0100:1487)
D WriterTimeBeg 6A OVERLAY(SPLA0100:1494)
D WriterDateEnd 7A OVERLAY(SPLA0100:1500)
D WriterTimeEnd 6A OVERLAY(SPLA0100:1507)
D JobSysName 8A OVERLAY(SPLA0100:1513)
D AuxStorPoolDv 10A OVERLAY(SPLA0100:1521)
D ExpireDate 7A OVERLAY(SPLA0100:1531)
于 2018-04-04T16:39:30.757 回答
0
例如，CEEHDLR/CEEHDLU (un) 为当前堆栈（入口）帧注册一个用户编写的条件处理程序。
于 2011-01-18T16:11:02.730 回答