HP Fortran Programmer Guide (766160-001, March 2014)

Vectorization........................................................................................................................103
Using the +Ovectorize option............................................................................................103
Controlling vectorization locally.........................................................................................104
Calling BLAS library routines.............................................................................................105
Controlling code generation for performance...........................................................................106
7 Writing HP-UX applications......................................................................107
Accessing command-line arguments........................................................................................107
Calling HP-UX system and library routines................................................................................108
Using HP-UX file I/O.............................................................................................................108
Stream I/O using FSTREAM..............................................................................................108
Performing I/O using HP-UX system calls.............................................................................108
Establishing a connection to a file......................................................................................108
Obtaining an HP-UX file descriptor.....................................................................................109
8 Calling C routines from HP Fortran............................................................110
Data types...........................................................................................................................110
Unsigned integers............................................................................................................111
Logicals..........................................................................................................................111
Complex numbers............................................................................................................112
Derived types..................................................................................................................113
Pointers...........................................................................................................................113
Argument-passing conventions................................................................................................113
Case sensitivity.....................................................................................................................114
Arrays.................................................................................................................................116
Memory layout of a two-dimensional array in Fortran and C..................................................116
C strings..............................................................................................................................118
C null-terminated string.....................................................................................................118
Fortran hidden length argument.........................................................................................118
Passing a string...............................................................................................................118
File handling........................................................................................................................120
Sharing data........................................................................................................................122
9 Using Fortran directives...........................................................................123
Directive syntax....................................................................................................................123
Using HP Fortran directives....................................................................................................123
$HP$ ALIAS....................................................................................................................124
$HP$ CHECK_OVERFLOW...............................................................................................126
$HP$ LIST.......................................................................................................................127
$HP$ OPTIMIZE..............................................................................................................127
Compatibility directives.........................................................................................................128
Controlling vectorization...................................................................................................128
Controlling parallelization.................................................................................................129
Controlling dependence checks.........................................................................................129
Controlling checks for side effects.......................................................................................129
10 Migrating to HP Fortran.........................................................................131
Incompatibilities with HP FORTRAN 77...................................................................................131
Compiler limits................................................................................................................131
Command-line options not supported..................................................................................131
Format field widths...........................................................................................................132
Floating-point constants.....................................................................................................132
Intrinsic functions.............................................................................................................132
Procedure calls and definitions..........................................................................................133
Data types and constants..................................................................................................133
Input/output....................................................................................................................134
Directives........................................................................................................................134
Contents 5