Arguments Passed by Value, 150 | HP SunSoft Pascal 4.0 guide

7

When you compile the Pascal routine without the -calignoption, the program does not work correctly.

Compile with the -calignoption. The program now works correctly.

hostname% pc -c DayWeather.p

hostname% CC DayWeather.o DayWeatherMain.cc -lpchostname% a.out

day = ''

weather = ' Sun'

hostname% pc -calign -c DayWeather.p

hostname% CC DayWeather.o DayWeatherMain.cc -lpchostname% a.out

day = 'Sunday' weather = 'Sunny'

Arguments Passed by Value

C++ arguments can be passed by value. In this section, we describe how they work with Pascal.

150	Pascal 4.0 User’s Guide

Image 174

HP SunSoft Pascal 4.0 Arguments Passed by Value, Hostname% pc -c DayWeather.p, Hostname% pc -calign -c DayWeather.p, 150

Contents

Pascal 4.0 User’s Guide Trademarks Contents Pascal Compiler Contents Pic, -Kpicand -PIC, -KPIC Contents Vii Program Construction and Management Viii Separate Compilation C++-Pascal Interface Error Diagnostics XView Toolkit Xii Contents Xiii Math Libraries Xiv Figures Pascal 4.0 User’s Guide Tables Fortran Xviii Installation PrefaceOperating Environment Audience Organization Conventions Used in This Guide AaBbCc123 Shell Prompts in Command Examples Related DocumentationManual Documents in Hard Copy and in AnswerBook Readme FilesOther Related Documentation Hostname% imagetool floating-point.ps CD-ROM Introduction Standards Features Pascal CompilerCompatibility XView Toolkit Text EditorsDebuggers Native Language Support Internationalization Licensing Locale Pascal 4.0 User’s Guide Pascal Programs Simple Pascal Program Compiling the Program Hostname% mv a.out temp Running the ProgramRenaming the Executable File Hostname% pc -o temp temp.p An Interactive Pascal Program Hello, are you listening? Redirecting I/OHostname% pc -o copy copy.p Goodbye, I must go now Using a File Name as a File Variable Where Did My Program Fail? Using Pascal TracebackHostname% pc -o copy2 copy2.p Using a Sample Program with Segmentation Violation Compiling and Running the Program Using the -gOption Hostname% more a.out.trace Try compiling SegViol.p with -g Pascal Compiler Pc Version Number Compile and Link Sequence Hostname% mcs -p a.out grep Pascal Compiler Preprocessor cpp or cppas Language PreprocessorSource Optimizer File Name Extensions Accepted By pc Sufﬁx Description Hostname% pc -l rmc.p Option-Passing on the Command-LineOption-Passing in the Program Text Hostname% pc -o rmc rmc.p Option Description Options Hostname% pc options.p Bbinding Bsdmalloc Cg92 CalignCg89 Cond Config Dname=def Dalign DryrunFast Fnonstd FnsFround=r Ftrap=t Hname Iname Help or -flagsIpathname Keeptmp Ldirectory Hostname% pc -l random.p Llib LibmieeeLibmil Misalign Nolib NativeNocx Nolibmil Notrace Olevel Hostname% limit datasize 16M Hostname% /usr/sbin/prtconf grep Memory OﬁlenameHostname% /usr/sbin/swap -s Hostname% pc -o myprog myprog.p -pg Using the -pOptionUsing the -pgOption Pic,-Kpic and -PIC,-KPIC Qoption QpathpathnameQproduce Rpathdir Pascal 4.0 User’s Guide Examples Hostname% pc -Rw rr.p Hostname% pc -Rw recvar.p Commands to compile and execute with.p Pascal main program, with.p with statementHostname% pc -Rw with.p Slevel SbfastHostname% pc -S rmc.p Temp=dir Hostname% pc -temp=. hello.p Time Hostname% pc -time hello.p Uname Xarch=a Pascal 4.0 User’s Guide Value Meaning Limit the instruction set to V8 architecture Xcache=c S1/l1/a1 S1/l1/a1s2/l2/a2 S1/l1/a1s2/l2/a2s3/l3/a3 Xchip=c Example -xcache=16/32/41024/32/1speciﬁes the following Xcg89 Xcg92 Xlibmieee XildoffXildon Xlibmil XMerge XlibmoptXlicinfo Xnolib Xpg Xprofile=p -xprofileValues Xregs=r Example -xregs=appl,no%float Xsafe=mem XsbXsbfast Xspace Xtarget=t XtargetExpansions Pascal 4.0 User’s Guide Pascal Compiler Ztext Program Construction Management Units Using Program Units and Module Units Compiling with Units Hostname% pc programunit.p moduleunit.pProgram Construction and Management Using Units and Header Files Sharing Variables Between Units Here is a program unit that declares a variable Program Construction and Management Libraries Separate Compilation Working with Units Using Program Units Using Module UnitsSharing Variables and Routines Across Multiple Units Program unit Compiling without the -xlOptionSharing Public Variables Separate Compilation Using extern Option to Share Routines Using include Files to Share Variables and Routines Module unit, incmod.p, which also includes the ﬁle Commands to compile and execute incprog.p and incmod.pProgram unit, incprog.p, which includes the ﬁle Hostname% pc incprog.p incmod.p Using the -xlOption Using public var Declarations Commands to compile and execute pubvarprog.p and pubvarmod.p Using the define Variable Attribute Using the define Declaration Commands to compile and execute defvarprog.p and defvarmod.p Using include Files Module unit Program unit, incprog2.p Module unit, incmod2.p Using extern Commands to compile and execute incprog2.p and incmod2.pProgram unit, extprog.p Commands to compile and execute extprog.p and extmod.p Sharing Declarations in Multiple UnitsModule unit, extmod.p Pascal 4.0 User’s Guide C-Pascal Interface Compilation of Mixed-Language Programs Compatibility of Types for C and Pascal Hostname% cc -c myc.c Hostname% pc -calign myc.o mypascal.p Precautions with Compatible Types Character StringsC-Pascal Interface Aggregate Types IncompatibilitiesArray Indexes Enumerated Types Procedure Calls C-Pascal General Parameter Passing in C and PascalPascal Set Types Commands to compile and execute Samp.p Variable Parameters Pascal procedure, SimVar.p Simple Types without -xl Simple Types with -xl Commands to compile and execute SimVar.p and SimVarMain.cPascal procedure Strings of Characters Commands to compile and execute StrVar.p and StrVarMain.c Fixed ArraysC main program Pascal procedure, FixVec.p Commands to compile and execute FixVec.p and FixVecMain.c Day = Univ Arrays 100 Conformant Arrays C-Pascal Interface 101 Example 1 Single-Dimension Array 102 Example 2 Multi-Dimension Array C-Pascal Interface 103 Example 3 Array of Characters 104 Records and Structures C-Pascal Interface 105 Commands to compile and execute StruChr.p and StruChrMain.c 106 Pascal routine C-Pascal Interface 107 Variant Records 108 Commands to compile and execute VarRec.p and VarRecMain.c C-Pascal Interface 109 Pascal Set Type 110 Pascal intset Type C-Pascal Interface 111 Value Parameters 112 Commands to compile and execute SimVal.p and SimValMain.c C-Pascal Interface 113 Arrays 114 Pascal function Function Return ValuesSimple Types C-Pascal Interface 115 Input and Output Commands to compile and execute RetReal.p and RetRealMain.cPascal procedure, IO.p C main program, IOMain.c 116 C function, SimRef.c Procedure Calls Pascal-CHostname% cc IO.o IOMain.c -lpc C-Pascal Interface 117 118 C function, StrVar.c Pascal main program, StrVarMain.pC-Pascal Interface 119 Commands to compile and execute StrVar.c Incorrect use of string in static variable storage120 Pascal main program Commands to compile and execute FixVec.cC function, FixVec.c C-Pascal Interface 121 C function, UniVec.c 122 C function, IntCA.c C-Pascal Interface 123 Commands to compile and execute IntCA.c and IntCAMain.p C function, StruChr.c124 Calign StruChr.o StruChrMain.p Commands to compile and execute StruChr.c and StruChrMain.pStruChr.c Out C function, VarRec.c 126 Non-Pascal Procedures Commands to compile and execute VarRec.cC-Pascal Interface 127 128 C function, SimVal.c C-Pascal Interface 129 Commands to compile and execute SimVal.c 130 C function, RetReal.c Parameters That Are Pointers to ProceduresCommands to compile and execute RetReal.c and RetRealMain.p C function, ProcPar.c Procedures and Functions as Parameters 132 Pascal procedure, GloVar.p Global Variables in C and PascalC-Pascal Interface 133 C procedure, UseFilePtr.c File-Passing Between Pascal and C134 C-Pascal Interface 135 136 C++-Pascal Interface Sample Interface Compatibility of Types for C++ and Pascal Procedure Calls C++-PascalPascal procedure, Samp, in the ﬁle, Samp.p ++ Name Encoding Hostname% pc -c Samp.p Arguments Passed by ReferenceC++ main program, SampMain.cc C++-Pascal Interface 139 Pascal procedure, SampRef, in the ﬁle, Samp.p Simple Types without the -xlOption140 C++ main program Commands to compile and execute SamRef.p and SamRefMain.ccSimple Types with the -xlOption Hostname% pc -c SamRef.p 142 Commands to compile and execute StrRef.p and StrRefMain.cc Hostname% pc -c StrRef.pC++-Pascal Interface 143 Hostname% pc -c FixVec.p 144 C++-Pascal Interface 145 -calignoption Hostname% pc -c DaysOfWeek.p146 Commands to compile and execute StruChr.p Hostname% pc -c StruChr.pC++-Pascal Interface 147 148 C++-Pascal Interface 149 Hostname% pc -calign -c DayWeather.p Arguments Passed by ValueHostname% pc -c DayWeather.p 150 C++-Pascal Interface 151 Commands to compile and execute SimVal.p 152 Commands to compile and execute RetReal.p Hostname% pc -c RetReal.pC++-Pascal Interface 153 Pascal function, IO.p Input and OutputHostname% pc -c RetShortReal.p 154 Hostname% CC IO.o IOMain.cc -lpc hostname% a.out Procedure Calls Pascal-C++C++ main program, IOMain.cc C++-Pascal Interface 155 Simple Types Passed by Reference C++ function, SimRef.cc156 C++-Pascal Interface 157 C++ function, SimVal.cc 158 Commands to compile and execute SimVal.cc C++-Pascal Interface 159 C++ function, RetReal.cc 160 Global Variables in C++ and Pascal Pascal procedure, GloVar.p C++ main program, GloVarMain.ccCommands to compile and execute GloVar.p and GloVarMain.cc C++-Pascal Interface 161 C++ procedure Pascal File Pointers to C++162 FORTRAN-Pascal Interface Compiler Mixed-Language Programs Compatibility of Types for Fortran and Pascal 164 Real Integer Integer*2 FORTRAN-Pascal Interface 165 166 Multidimensional Arrays General Parameter-Passing in Fortran and PascalFORTRAN-Pascal Interface 167 Procedure Calls FORTRAN-Pascal 168 Commands to compile and execute SimVar.p Fortran main programFORTRAN-Pascal Interface 169 Pascal procedure, StrVar.p Fortran main program, StrVarmain.f170 Commands to compile and execute StrVar.p and StrVarmain.f Fortran main program, FixVecmain.fFORTRAN-Pascal Interface 171 Commands to compile and execute FixVec.p 172 Commands to compile and execute UniVec.p and UniVecmain.f FORTRAN-Pascal Interface 173 Commands to compile and execute IntCA.p 174 Commands to compile and execute ChrCA.p Fortran main program, ChrCAmain.fFORTRAN-Pascal Interface 175 176 FORTRAN-Pascal Interface 177 178 FORTRAN-Pascal Interface 179 180 FORTRAN-Pascal Interface 181 Commands to compile and execute SimVal.p and SimValmain.f 182 Pointers Pascal procedure, ChrCAx.pCommands to compile and execute ChrCAx.p FORTRAN-Pascal Interface 183 Commands to compile and execute PastPtr.p 184 Procedure Calls Pascal-FORTRAN Fortran main program, RetRealmain.fFORTRAN-Pascal Interface 185 Fortran subroutine 186 FORTRAN-Pascal Interface 187 Fortran subroutine, StrVar.f 188 Hostname% f77 -c StrVar.f Commands to compile and execute StrVar.f and StrVarmain.pCharacter Dummy Arguments Hostname% pc StrVar.o StrVarmain.p -lpfc -lF77 Following example illustrates this method 190 Commands to compile and execute FixVec.f FORTRAN-Pascal Interface 191 Fortran subroutine, UniVec.f Pascal main program, UniVecmain.p192 Commands to compile and execute UniVec.f and UniVecmain.p Hostname% f77 -c UniVec.fFORTRAN-Pascal Interface 193 Fortran subroutine, StruChr.f 194 Hostname% pc StruChr.o StruChrmain.p -lpfc -lF77 Commands to compile and execute StruChr.f and StruChrmain.pHostname% f77 -c StruChr.f FORTRAN-Pascal Interface 195 196 FORTRAN-Pascal Interface 197 198 FORTRAN-Pascal Interface 199 200 Hostname% pc PassPtr.o PassPtrmain.p -lpfc -lF77 Commands to compile and execute PassPtr.f and PassPtrmain.pHostname% f77 -c PassPtr.f Fortran function, RetReal.f Commands to compile and execute RetReal.f and RetRealmain.p Routines as Parameters202 FORTRAN-Pascal Interface 203 204 Error Diagnostics Compiler Syntax ErrorsIllegal Characters String Errors Digits in Real Numbers206 Replacements, Insertions, and Deletions Error Diagnostics 207Hostname% pc synerr.p Expected Symbols and Malformed Constructs Undeﬁned or Improper Identiﬁers208 Hostname% pc synerr2.p Error Diagnostics 209Expected and Unexpected End-of-ﬁle Pascal program, mism.p Incompatible Types Compiler Semantic ErrorsFormat of the Error Diagnostics 210 Procedure and Function Type Errors Error Diagnostics 211Scalar Class Scalar Error Messages Expression Diagnostics212 This program generates the following error messages Error Diagnostics 213 Type Equivalence 214 Error Diagnostics 215 Unreachable StatementsPascal program, unreached.p Unused Variables, Constants, Types, Labels, and Routines Goto StatementUninitialized Variables Hostname% pc unreached.p Compiler Panics, I/O Errors Runtime ErrorsError Diagnostics 217 218 Error Diagnostics 219 220 XView Toolkit Overview Object-Oriented Programming ToolsObjects 222 Pascal Interface Drawable Object Window IconXView Toolkit 223 Header Files Attribute ProceduresCompiling with Libraries Names Attribute Lists XView Toolkit 225 Here, mymenu is an object of type XVobject HandlesData Types 226 An Example Conversion of C to PascalCoding Fragment XView Toolkit 227 Pascal 228 Sample Translation of an XView Function to Pascal XView Toolkit 229 Sample Program 230 Menu Demo Program XView Toolkit 231 Panelbutton 232 Math Libraries Contents of the Math Libraries Libm Functions Math Libraries 235 Ieee Support Functions 236 Ieeefunctions IeeevaluesMath Libraries 237 Sparc Libraries Ieeeretrospective238 Arithmetic Exceptions Math Libraries 239 Math Library Exception-Handling Function matherr 240 Math Libraries 241 Libsunmath Support for Ieee Modes and Exceptions 242 Math Libraries 243 244 Pascal Preprocessor Conditional Variables Compiler Directives 246 %config Directive Pascal Preprocessor 247 Hostname% pc -xl config.p hostname% a.out 248 %debug Directive Output when you deﬁne twoOutput when you deﬁne foo Pascal Preprocessor 249 %else Directive Hostname% pc -xl -cond debug.p hostname% a.out250 Pascal program, ifthenelse.p Hostname% pc -xl -config red ifthenelse.p hostname% a.out%elseif Directive Pascal Preprocessor 251 Pascal program Hostname% pc -xl -config blue elseif.p hostname% a.out%elseifdef Directive 252 Pascal Preprocessor 253 %enable Directive Hostname% pc -xl -config bird2 ifdef.p hostname% a.out254 %endif Directive %error DirectiveHostname% pc -xl enable.p hostname% a.out Pascal Preprocessor 255 Error.p %exit Directive256 %if Directive Hostname% pc -xl exitdirective.p hostname% a.outPascal Preprocessor 257 %ifdef Directive 258 %include Directive Pascal Preprocessor 259 %list Directive Module unit, includemod.p260 Pascal program, list.p Pascal Preprocessor 261 %nolist Directive List.p262 %warning Directive %slibrary Directive%var Directive Pascal Preprocessor 263 Output when you compile warning.p without the -configoption Pc -xl warning.p264 Error Messages 266 Error Messages 267 Fourth argument to function must be of type type, not type 268 Error Messages 269 Function requires a to be an unpacked array, not type 270 Error Messages 271 272 Error Messages 273 274 Error Messages 275 Identiﬁer Unknown option for procedure pointer ignored option 276 Error Messages 277 278 Error Messages 279 280 Error Messages 281 Cannot mix sets with integers and reals as operands of type 282 Error Messages 283 284 Error Messages 285 286 Error Messages 287 288 Error Messages 289 Multiply defined label in case, lines number and number 290 Error Messages 291 292 Error Messages 293 OUT 294 Error Messages 295 296 Index 297 298 Index 299 300 Index 301 302 Index 303 304 Index 305 306 Index 307 Marques