%EOF (Return End or Beginning of File Condition)

%EOF{(file_name)}

%EOF returns '1' if the most recent read operation or write to a subfile ended in an end of file or beginning of file condition; otherwise, it returns '0'.

The operations that set %EOF are:

The following operations, if successful, set %EOF(filename) off. If the operation is not successful, %EOF(filename) is not changed. %EOF with no parameter is not changed by these operations.

When a full-procedural file is specified, this function returns '1' if the previous operation in the list above, for the specified file, resulted in an end of file or beginning of file condition. For primary and secondary files, %EOF is available only if the file name is specified. It is set to '1' if the most recent input operation during *GETIN processing resulted in an end of file or beginning of file condition. Otherwise, it returns '0'.

This function is allowed for input, update, and record-address files; and for display files allowing WRITE to subfile records.

For more information, see File Operations or Built-in Functions.

Figure 214. %EOF without a Filename Parameter

 *..1....+....2....+....3....+....4....+....5....+....6....+....7...+....
F*Filename+IPEASFRlen+LKlen+AIDevice+.Keywords+++++++++++++++++++++++++
 * File INFILE has record format INREC
FINFILE    IF   E             DISK

 /FREE
    READ INREC;  // read a record
    IF  %EOF;
                 // handle end of file
    ENDIF;
 /END-FREE

Figure 215. %EOF with a Filename Parameter

 *..1....+....2....+....3....+....4....+....5....+....6....+....7...+....
 * This program is comparing two files

F*Filename+IPEASFRlen+LKlen+AIDevice+.Keywords+++++++++++++++++++++++++
FFILE1     IF   E             DISK
FFILE2     IF   E             DISK

 * Loop until either FILE1 or FILE2 has reached end-of-file
 /FREE
    DOU %EOF(FILE1) OR %EOF(FILE2);
       // Read a record from each file and compare the records
 
       READ REC1;
       READ REC2;
       IF %EOF(FILE1) AND %EOF(FILE2);
          // Both files have reached end-of-file
          EXSR EndCompare;
 
       ELSEIF %EOF(FILE1);
          // FILE1 is shorter than FILE2
          EXSR F1Short;
 
       ELSEIF %EOF(FILE2);
          // FILE2 is shorter than FILE1
          EXSR F2Short;
 
       ELSE;
          // Both files still have records to be compared
          EXSR CompareRecs;
       ENDIF;
    ENDDO;
  // ...
 /END-FREE

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