Open Watcom FORTRAN 77 Language Reference

Language Reference
3. This specifier becomes defined with a value only if the file name specified in the FILE=
specifier is an acceptable file name and the named file exists. Also, no error condition can occur
during the execution of the INQUIRE statement.
4. This specifier becomes defined with a value if and only if od becomes defined with the value
.TRUE.. Also, no error condition can occur during the execution of the INQUIRE statement.
5. This specifier may become defined with a value only if od becomes defined with the value
.TRUE.. However, there may be other conditions under which this specifier does not become
defined with a value. In other words, (5) is a necessary, but not sufficient condition. For
example, blnk is undefined if the file is not connected for formatted input/output.
2.55.5 Definition Status of Specifiers - Inquire by Unit
The following table summarizes which specifier variables or array elements become defined with values
under what conditions when using the UNIT= specifier.
IOSTAT = ios (1)
EXIST = ex (2)
OPENED = od (2)
NUMBER = num (3)
NAMED = nmd (3)
NAME = fn (3)
ACCESS = acc (3)
SEQUENTIAL = seq (3)
DIRECT = dir (3)
FORM = fm (3)
FORMATTED = fmt (3)
UNFORMATTED = unf (3)
RECL = rcl (3)
NEXTREC = nr (3)
BLANK = blnk (3)
ACTION = act (3)
CARRIAGECONTROL = cc (3)
RECORDTYPE = rct (3)
BLOCKSIZE = bl (3)
1. The IOSTAT= specifier variable is always defined with the most recent error status. If an error
occurs during execution of the INQUIRE statement then the error status is defined with a
positive integer; otherwise the status is that of the most recent input/output statement which
referenced that unit.
2. This specifier always becomes defined unless an error condition occurs.
3. This specifier becomes defined with a value only if the specified unit exists and if a file is
connected to the unit. Also, no error condition can occur during the execution of the INQUIRE
statement.
For more information on input/output, see the chapter entitled "Input/Output" on page 215.
98 INQUIRE Statement