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Full Discussion: While loop and IFS?
Top Forums Shell Programming and Scripting While loop and IFS? Post 302519298 by sid22 on Tuesday 3rd of May 2011 03:25:27 PM
Old 05-03-2011
While loop and IFS?
Hi,
Code:
while [ 1 -eq 1 ]; do
    echo "Please enter "
    read enter
    yyyy=${enter:0:4}
    mm=${enter:5:2}
    dd=${enter:8:2}
    result=`validateDate $yyyy $mm $dd`

When does the loop keeping repeating till?? till 1 is equal to 1?

what does this mean "${enter:0:4}" .The 0 and 4 part??

What does IFS do?? so if its set to IFS='' . What happens?? or what can you do with it??
Last edited by Scott; 05-03-2011 at 04:32 PM.. Reason: Code tags
 

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LEARN ABOUT OSF1

from

from(1) 						      General Commands Manual							   from(1)

NAME

       from - Shows whom mail messages are from

SYNOPSIS

       from [-s sender] [user]

       The from command prints out the mail header lines in your mailbox file.

OPTIONS

       Prints headers for mail sent by sender.	Specifies a mail spool directory.

	      Use this flag if you want to examine a mailbox in a directory other than /usr/spool/mail, which is the system default.

DESCRIPTION

       If user is specified, then user's mailbox is examined instead of your own.

EXAMPLES

       To display the message headings in your mailbox, enter: from

	      The  names  of  the  senders and the message dates are displayed.  To display the message headings for mail sent by a specific user,
	      enter: from -s dale

	      Displays only the message headings of the messages sent from user dale.  To display the message headings in a specific user's  mail-
	      box, enter: from dawn

	      The message headings from user dawn's mailbox are displayed, provided you have read permission for dawn's mailbox.

FILES

       User mailbox files.

SEE ALSO

       Commands:  biff(1), mail(1), mailx(1)

																	   from(1)
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