Section 13,27: ENDFILE

 Writes an end-of-file record to the specified unit.  Statement
 format:

    ENDFILE ([UNIT=]u[,ERR=s][,IOSTAT=ios])
    ENDFILE u

    u    Is an integer variable or constant specifying 
         the logical unit number of the file, optionally  
         prefaced by UNIT=.  UNIT= is required if unit is 
         not the first I/O specifier.

    s    Is the label of a statement to which control is 
         transferred if an error occurs, prefaced by ERR=.

    ios  Is an integer variable to which the completion 
         status of the I/O operation is returned, prefaced 
         by IOSTAT= (a zero if no error occurs; a positive
         value if an error occurs).

 If the unit specified in the ENDFILE statement is not open, the
 default file is opened for unformatted output.

 An end-of-file record consists of one byte with the ASCII value 26
 (Ctrl/Z).  An end-of-file record can be written only to sequential
 organization files that are accessed as formatted sequential files
 or unformatted segmented sequential files.

 An ENDFILE statement must not be specified for a file that is open
 for direct access.  End-of-file records should not be written in
 files that are read by programs written in a language other than
 Fortran.