keifer@uiucdcs.CS.UIUC.EDU (12/02/85)
Field 3 (byte offset 11) of the file directory entry, bit 0 controls write protection. Turn this bit on for write-protect (read-only). directory entry: Field Offset Desc. 1 0 File name 2 8 fielanem extension 3 11 attribute etc. Attribute Byte: 76543210 .......1 Read-only ......1. Hidden .....1.. System ....1... Volume label ...1.... subdirectory ..1..... archive .1...... unused 1....... unused This information is from Peter Norton's "Programmer's Guide to the IBM PC" (a swell book). G. P. Seaburg c/o K. Keifer Univ. of Illinois
bill@hp-pcd.UUCP (bill) (12/02/85)
All you need to do is set the file's Read-Only attribute bit. The easiest way to do this is to use one of the many available programs that let you monkey with file attributes -- CHMODE (aka CHMOD) is probably the most popular; TCHMOD is another I know of, as well as one of the programs that comes with the Norton Utilities (I forget its name, I think it's FA.COM or something like that). With CHMODE, you just say chmode +r filename Kind of like the way you'd do it with Unix. If you want to do it programmatically, there's a dos function called Get/Set Attribute. Unfortunately, I don't have its specifics in front of me so I'll leave it to someone else to describe it to you, or you can look it up in any handy-dandy MS-DOS Programmer's Reference Manual ... bill frolik hp-pcd!bill