Q25996: No EOF (CTRL+Z) Marker Written at End of Sequential File
Article: Q25996 Product(s): See article Version(s): 4.00 4.00b 4.50 Operating System(s): MS-DOS Keyword(s): ENDUSER | TAR68492 B_BasicCom | mspl13_basic Last Modified: 7-JUN-1989 Programs compiled in QuickBASIC Version 4.00, 4.00b, or 4.50, or in BASIC Compiler Version 6.00 or 6.00b, don't add an end-of-file (EOF) marker [chr$(26), or CTRL+Z] at the end of output or appended sequential files. Sequential files created with QuickBASIC Version 4.00 (and later) and BC 6.00 (and later) programs will correctly read into programs compiled in QuickBASIC Version 3.00 even though there is no EOF marker, but other applications (those that follow the DOS Versions 1.x standard for EOF) may generate an "input past end" error looking for the CTRL+Z. This is not an error in the QuickBASIC or compiled BASIC software. The lack of writing CTRL+Z to mark the end of the file was a deliberate change to allow QuickBASIC programs to read files that contain embedded CTRL+Z's. CTRL+Z's can often occur with binary files and screen files saved with the BSAVE command. The use of CTRL+Z to mark the end of file is a DOS Versions 1.x application standard (which was carried over from the CP/M-80 operating system). Applications written for DOS Versions 2.x and 3.x standards use the exact number of bytes in the file to determine the end of file, which is a more practical design. This file size is stored for each file in the File Allocation Table (FAT) on each disk. You can write your own CTRL+Z to the end of a file by writing a program that opens the file for append and sends a chr$(26) to the file.
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