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-
- NO Charles Petzold
- Command PC Magazine Vol 5, No 9
- Copyright 1986 Ziff-Davis Publishing Company
- ______________________________________________________
-
- Purpose: Excludes specified files in a subdirectory
- from the action of a command.
-
- Format: NO filespec Command [parameter]
-
- Remarks: NO.COM is designed for situations in which
- you want to apply a command such as DELete or
- COPY to all the files in a directory except
- one or two (or a class of) files. For
- example,
-
- NO *.BAS COPY *.* A:
-
- copies all the files in your current
- subdirectory to drive A: except for those
- that have a .BAS extension.
-
- To exclude more than one file (or category)
- you must use a separate NO command for each
- on the command line. Thus,
-
- NO *.ASM NO *.COM DEL *.*
-
- deletes all files in the current directory
- except those with .ASM or .COM extensions.
-
- Notes:
-
- 1. NO.COM should not be used in conjunction
- with the PC-DOS BACKUP and RESTORE
- commands. This is because NO operates
- by temporarily setting the "hidden" file
- attribute bit on the files to be
- excluded from the main command, then
- unhiding the files after the main
- command has been executed. Since the
- DOS BACKUP/RESTORE operation acts on
- hidden and unhidden files alike, NO.COM
- cannot be used to exclude files from
- BACKUP/RESTORE. RESTORE, indeed, will
- restore the supposedly excluded files as
- hidden, overwriting the originals.
-
- 2. While NO.COM provides full path support
- (and so requires the use of DOS 2.0 or
- later), it is a good policy when using
- NO to use CHDIR to make the directory
- that contains the files on which you
- wish to operate the current directory.
-
- For example, suppose you are in your
- root directory, one of whose subdirec-
- tories is \BASIC. If you were to enter
- the command
-
- NO *.BAS DEL \BASIC\*.*
-
- you would not delete all the files in
- the \BASIC subdirectory except those
- with a .BAS extension, as you might have
- intended to do. To do this from the
- root directory you would have had to
- enter
-
- NO \BASIC\*.BAS DEL \BASIC\*.*
-
- This complete filespec would tell NO
- that it had to protect files in the
- \BASIC, not in the current (i.e., root)
- directory.
-
- If you follow our recommendation and
- enter
-
- CD \BASIC
- NO *.BAS DEL *.*
-
- thus making \BASIC your current
- directory before you start deleting, you
- will then clean out all but the .BAS
- files, just as you intended.
-
- 3. Should a parity check error, power
- outage, or system crash occur during the
- brief period between the times NO hides
- and subsequently unhides the protected
- files, those files will subsequently
- seem to have disappeared. They are not
- lost; only hidden from a DIR listing.
- Use ATTR.COM (included in this set of
- utilities) to change their hidden
- status.
-
-
-