Open Watcom FORTRAN 77 Language Reference

Language Reference
Example:
LOGICAL EX, OD
CHARACTER*30 FN
INQUIRE( UNIT=7, EXIST=EX, OPENED=OD, NAME=FN )
In the above example, information is requested on unit 7. In particular, we want to know if the unit exists,
whether it is connected to a file, and, if so, what the file name is.
2.55.3 Inquiry Specifiers
The following inquiry specifiers are supported.
IOSTAT = ios
ERR = s
EXIST = ex
OPENED = od
NUMBER = num
NAMED = nmd
NAME = fn
ACCESS = acc
SEQUENTIAL = seq
DIRECT = dir
FORM = fm
FORMATTED = fmt
UNFORMATTED = unf
RECL = rcl
NEXTREC = nr
BLANK = blnk
As an extension to the FORTRAN 77 language, the following inquiry specifiers are also supported.
ACTION = act
CARRIAGECONTROL = cc
RECORDTYPE = rct
BLOCKSIZE = bl
IOSTAT = ios is an input/output status specifier. The integer variable or integer array element ios is
defined with zero if no error condition exists or a positive integer value if an error condition
exists.
ERR = s
EXIST = ex
is an error specifier and s is a statement label. When an error occurs, execution is
transferred to the statement labelled by s.
ex is a logical variable or logical array element.
Inquire by file: The value .TRUE. is assigned if a file exists with the specified name;
otherwise the value .FALSE. is assigned.
Inquire by unit: The value .TRUE. is assigned if the specified unit exists; otherwise the
value .FALSE. is assigned.
OPENED = od od is a logical variable or logical array element.
94 INQUIRE Statement