求fortran Error:Not a valid value for the char-expr in this c

status
Character*(*).Describes the nature of the file to be opened.Can be one of the following:
●'OLD' The file must already exist.If the file exists,it is opened.If it does not exist,an I/O error occurs.
●'NEW' The file must not already exist.If the file does not exist,it is created.If it exists,an I/O error occurs.
●'SCRATCH' If you omit the file parameter when opening a file,the value of status defaults to 'SCRATCH'.Scratch files are temporary.They are deleted when the unit is closed or when the program terminates.
●'REPLACE' The file opened replaces one of the same name.If there is no existing file of the same name,a new file is created.
●'UNKNOWN' (Default) The run-time system first attempts to open the file with status equal to 'OLD',and then with status equal to 'NEW'.If the file exists,it is opened; if it does not exist,it is created.
●Using STATUS= 'UNKNOWN' avoids any run-time errors associated with opening an existing file using STATUS='NEW' or opening a nonexistent file using STATUS='OLD'.
x05Values of status affect only disk files,and are ignored for devices such as the keyboard or the printer.
没有发现'readonly'这个选项.