Open Watcom FORTRAN 77 Language Reference

Language Reference
FILE = fin
fin is a character expression whose value when trailing blanks are removed is the name of
a file to be connected to the specified unit. If this specifier is omitted and the unit is not
connected to a file, it becomes connected to a file determined by Open Watcom FORTRAN
77. The name established by Open Watcom FORTRAN 77 is described in the section
entitled "Units" on page 219 of the chapter entitled "Input/Output"
STATUS = sta
sta is a character expression whose value when trailing blanks are removed is ’OLD’,
’NEW’, ’SCRATCH’, or ’UNKNOWN’.
OLD
NEW
SCRATCH
UNKNOWN
When OLD is specified, a FILE= specifier must be given. The file
must exist.
When NEW is specified, a FILE= specifier must be given. The file
must not exist. Successful execution of the OPEN statement creates the
file and changes the status to OLD.
SCRATCH may only be specified for an unnamed file (i.e. FILE= is
not allowed). When the file is closed, it is deleted.
If UNKNOWN is specified, the status is ignored. If the STATUS=
specifier is omitted then UNKNOWN is assumed.
ACCESS = acc
acc is a character expression whose value when trailing blanks are removed is
’SEQUENTIAL’ or ’DIRECT’. It specifies the access method for the file. If the
ACCESS= specifier is omitted then ’SEQUENTIAL’ is assumed. If the file exists then the
access method must be in the set of allowed access methods for the file. If the file does not
exist then the file is created with a set of allowed access methods that includes the specified
access method.
Open Watcom FORTRAN 77 also supports access ’APPEND’ which is a form of
sequential access in which the file is positioned at the endfile record. The file must exist or
the append access method must be in the set of allowed access methods for the file. In all
other respects, the file is treated as if ’SEQUENTIAL’ had been specified.
FORM = fm
RECL = rcl
fm is a character expression whose value when trailing blanks are removed is
’FORMATTED’ or ’UNFORMATTED’. It specifies that the file is being connected for
formatted or unformatted input/output. If the FORM= specifier is omitted and the file is
being connected for direct access then ’UNFORMATTED’ is assumed. If the FORM=
specifier is omitted and the file is being connected for sequential access then
’FORMATTED’ is assumed. If the file exists then the specified form must be included in
the set of allowed forms for the file. If the file does not exist then the file is created with a
set of allowed forms that includes the specified form.
rcl is an integer expression whose value must be positive. It specifies the length of each
record in a file being connected for direct access. If the file is being connected for direct
access, this specifier must be given; otherwise it must be omitted. Open Watcom
FORTRAN 77 allows the RECL= specifier for files opened for sequential access.
112 OPEN Statement