HP Fortran Programmer's Reference

Phil Atley 9 27 35 49
Harriet Myrle 84 78 93 95 97 92 84 93
Pete Hartley 67 54 58 71 93 58
I/O and file handling
Example programs
Here are the command lines to compile and execute the program, along with the output from
asamplerun:
$ f90 nonadvance.f90
$ a.out
Name Average
--------------------------
Sandra Delford 86
Joan Arunsoelton 57
Herman Pritchard 68
Felicity Holmes 78
Anita Jayson 85
Phil Atley 30
Harriet Myrle 89
Pete Hartley 66
File access
The following example, file_access.f90, illustrates both sequential and direct access on
external files. The file opened for direct access is a scratch file. The comments explain what
the program does.
Example 8-4 file_access.f90
! This program uses an external file and a scratch file to
! insert a number into a list of numerically sorted numbers.
! The sorted list is held in a external file. The program uses
! the scratch file as a temporary holding place. The program
! uses direct access method with the scratch file.
PROGRAM main
REAL :: number_to_insert, number_in_list
INTEGER :: rec_num, ios1, ios2, i
! Initialize counter.
rec_num = 0
! ios1 must be initialized to 0 so that the error-handling
! section at the end of the program will work correctly
ios1= 0
! Open the scratch file and the sequential data file
OPEN (18, FILE='list', STATUS='UNKNOWN', IOSTAT=ios1, ERR=99)
OPEN (17, STATUS='SCRATCH', ACCESS='DIRECT', FORM='FORMATTED',
&
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