A subroutine which can be called from FORTRAN to open an unblocked binary file and return a suitable file pointer for use in calls to the other PB subroutines. The return status code must be checked after calling the subroutine.
The format and arguments for the subroutine are:
SUBROUTINE PBOPEN(KUNIT, FILENAME, MODE, KRET)
Input arguments are CHARACTERs.
| FILENAME | Character string giving a Unix filename |
| MODE | Character describing the mode of access to the file: `r' for read, `r+' for read and write, `w' for write, `a' for append |
Output arguments are INTEGERs.
| KUNIT | Index in an internal array of a C file pointer for the file. Note that this is not the same as, or compatible with, a Fortran unit number as used in Fortran file-handling statements such as OPEN, READ, .... |
| KRET | Status return code:
0, successful
-1, could not open the file, eg it does not exist, or does not have suitable
permission for the requested access
-2, invalid filename
-3, invalid open mode specified |