bobc@killer.DALLAS.TX.US (Bob Calbridge) (07/21/88)
Okay, I give up. What is the function of the archive bit? Does this tell the opsys to do some auditing? The furschluginner book tells you how to set it but not what it's for. Also in passing......is there a way to copy protect specific files? Even something low level, just to keep the geeks out. Best, Bob
scott@clsib21.UUCP (Scott P. Herzig) (07/21/88)
In article <4873@killer.DALLAS.TX.US>, bobc@killer.DALLAS.TX.US (Bob Calbridge) writes: > Okay, I give up. What is the function of the archive bit? The bit is set by the BACKUP program to indicate whether or not a file has been archived. This makes it easy to spot when a backup has been done and what's been saved. -- Scott P. Herzig, CLSI, Inc. 320 Nevada Street Newtonville, MA 02160 UUCP: {...}bbn!clsib21!scott Internet: scott%clsib21.uucp@bbn.com
simcha@humming.UUCP (Simcha Lerner) (07/22/88)
In article <4873@killer.DALLAS.TX.US> bobc@killer.DALLAS.TX.US (Bob Calbridge) writes: >Okay, I give up. What is the function of the archive bit? Does this >tell the opsys to do some auditing? The furschluginner book tells you >how to set it but not what it's for. >Also in passing......is there a way to copy protect specific files? >Even something low level, just to keep the geeks out. > >Best, >Bob The archive bit is set every time the o/s updates a file. This is useful for backup programs that only want to archive files that have been modified since the last time they were backed up. (Read your DOS manual entry for the backup command for more info.) There is no easy way to copy protect s/w without getting involved with non-standard formatting (for floppy disks). The closest one can get to copy protecting in a DOS transparent fashion is to have code that installs the file, and patches some information into the file that is based on the absolute track/sector location(s) of the file. Efforts to copy this file will cause it to be relocated. Be aware the disk defragmentation programs will clobber this unless you set the file's hidden attribute, in which case most will leave it alone. If you only want to keep novice users from getting at something, you can mark a file hidden and system, which will keep it out of dir and copy. Caveat on these two ideas is that if the file is on a floppy disk, diskcopy will still copy it. (Also, to open a file with hidden or system attribute, you have to set the file attributes used for the open call to match the file's.) Simcha Lerner harvard!humming!simcha
brown@nicmad.UUCP (Mr. Video) (07/22/88)
In article <699@clsib21.UUCP> scott@clsib21.UUCP (Scott P. Herzig) writes: <In article <4873@killer.DALLAS.TX.US>, bobc@killer.DALLAS.TX.US (Bob Calbridge) writes: <> Okay, I give up. What is the function of the archive bit? < <The bit is set by the BACKUP program to indicate whether or not a file <has been archived. This makes it easy to spot when a backup has been <done and what's been saved. Sorry, you got it backwards. This bit is set whenever a file is written to, created, copied to another spot, etc. It is a flag that can tell backup programs that this file needs to be saved. It is reset by appropriate backup programs when the backup of the file is complete. This bit allows you to do selective backups, ie, only files that have changed, otherwise known as the incremental backup. -- harvard-\ att!terminus--\ Mr. Video ucbvax!uwvax.................!nicmad!brown rutgers-/ att-/ decvax--/
Ralf.Brown@B.GP.CS.CMU.EDU (07/22/88)
In article <233@humming.UUCP>, simcha@humming.UUCP (Simcha Lerner) writes: } (Also, to open a file with hidden or }system attribute, you have to set the file attributes used for the }open call to match the file's.) That is only true of the DOS 1.x FCB function calls. The DOS 2.x and 3.x file handle functions quite happily open hidden or system files for reading, provided you know the name (since the directory search won't find the files). Try typing "DEBUG IBMBIO.COM" from the root directory of a bootable disk. You just can't WRITE to a hidden or system file unless you properly set the file attributes for the open call--the DEBUG "W"rite command will fail In DOS 2.0 or later, the hidden and system bits both keep the file from being found in a directory search. However, the system bit additionally prevents the file from being executed (since the DOS system files are .COM), while the hidden bit does not. -- UUCP: {ucbvax,harvard}!cs.cmu.edu!ralf -=-=-=- Voice: (412) 268-3053 (school) ARPA: ralf@cs.cmu.edu BIT: ralf%cs.cmu.edu@CMUCCVMA FIDO: Ralf Brown 1:129/31 Disclaimer? I |Ducharm's Axiom: If you view your problem closely enough claimed something?| you will recognize yourself as part of the problem.
haugj@pigs.UUCP (Joe Bob Willie) (07/23/88)
In article <699@clsib21.UUCP> scott@clsib21.UUCP (Scott P. Herzig) writes: |In article <4873@killer.DALLAS.TX.US>, bobc@killer.DALLAS.TX.US (Bob Calbridge) writes: |> Okay, I give up. What is the function of the archive bit? | |The bit is set by the BACKUP program to indicate whether or not a file |has been archived. This makes it easy to spot when a backup has been |done and what's been saved. is it safe to assume that mess-dos clears the bit when it writes to the file? - john. -- jfh@rpp386.uucp (The Beach Bum at The Big "D" Home for Wayward Hackers) "Never attribute to malice what is adequately explained by stupidity" -- Hanlon's Razor
High-Mage@cup.portal.com (07/23/88)
The Archive bit if for backups. When you do a backup, the archive bit is turned off, when you change or add files, you can then do an Archive Backup, and only get those files which have been changed or added since the last backup. I recommend that you backup your hard drive fully at least once a month and do changed file or archive backups once or twice a week, the archive bit is for this purpose.
jcmorris@mitre-bedford.ARPA (Joseph C. Morris) (07/26/88)
In article <194@pigs.UUCP> haugj@pigs.UUCP (Joe Bob Willie) writes: > >is it safe to assume that mess-dos clears the [archive] bit when it >writes to the file? > No, it _sets_ the bit. The "archive" bit logic is: off - the file has been backed up by the BACKUP program on - the file has been opened for output since the last time it was backed up by BACKUP Perhaps the bit should be identified as "archive needed". Joe