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Full Discussion: How to check if file contains valid strings?
Top Forums UNIX for Dummies Questions & Answers How to check if file contains valid strings? Post 302774185 by rtagarra on Friday 1st of March 2013 11:01:54 AM
Old 03-01-2013
Thanks a lot for quick reply. I am sorry i could not understand much of the code:

Code:
while IFS="=" read v1 v2
do
        [[ "$v1" =~ ^[[:alpha:]]+$ ]] && echo "String: \"$v1\" is valid" || echo "String: \"$v1\" is invalid"
done < filename

Can you pls tell me what is IFS, read v1,v2 and what is the line you are doing inside loop. Can i store valid strings in an array and then check if the file contains only those words which belong to the array.
Last edited by Scrutinizer; 03-01-2013 at 12:54 PM.. Reason: code tags
 

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LEARN ABOUT OPENDARWIN

fsck_msdos

FSCK_MSDOS(8)						    BSD System Manager's Manual 					     FSCK_MSDOS(8)

NAME

     fsck_msdos -- DOS/Windows (FAT) file system consistency check

SYNOPSIS

     fsck_msdos -q special ...
     fsck_msdos -p [-f] special ...
     fsck_msdos [-fny] special ...

DESCRIPTION

     The fsck_msdos utility verifies and repairs FAT file systems (more commonly known as DOS file systems).

     The first form of fsck_msdos quickly checks the specified file systems to determine whether they were cleanly unmounted.

     The second form of fsck_msdos preens the specified file systems.  It is normally started by fsck(8) run from /etc/rc.boot during automatic
     reboot, when a FAT file system is detected.  When preening file systems, fsck_msdos will fix common inconsistencies non-interactively.  If
     more serious problems are found, fsck_msdos does not try to fix them, indicates that it was not successful, and exits.

     The third form of fsck_msdos checks the specified file systems and tries to repair all detected inconsistencies, requesting confirmation
     before making any changes.  The default behavior is to always ask for confirmation of each change.  Use the -n or -y options to override this
     default behavior.

     The options are as follows:

	   -q	   Causes fsck_msdos to quickly check whether the volume was unmounted cleanly.  If the volume was unmounted cleanly, then the
		   exit status is 0.  If the volume was not unmounted cleanly, then the exit status will be non-zero.  In either case, a message
		   is printed to standard output describing whether the volume was clean or dirty.

	   -f	   This option is ignored by fsck_msdos and is present only for compatibility with programs that check other file system types for
		   consistency.

	   -n	   Causes fsck_msdos to assume no as the answer to all operator questions, except ``CONTINUE?''.

	   -p	   Preen the specified file systems.

	   -y	   Causes fsck_msdos to assume yes as the answer to all operator questions.

SEE ALSO

     fsck(8)

BUGS

     fsck_msdos is still under construction.

NetBSD								  August 13, 1995							    NetBSD
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