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While loop and IFS?

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# 1  
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
# 2  
Old 05-03-2011
I hope this isn't homework...

The while loop: it loops as long as 1 equals 1 (which is forever) Smilie
# 3  
Old 05-03-2011
Quote:
Originally Posted by purdym
I hope this isn't homework...

The while loop: it loops as long as 1 equals 1 (which is forever) Smilie
lol.. it is not.. i am not asking anyone to do any coding for me Smilie.. just some coding i didnt understand so wanted to clarify.. SmilieSmilie
# 4  
Old 05-03-2011
Quote:
Originally Posted by sid22
Hi,
what does this mean "${enter:0:4}" .The 0 and 4 part??
Start at position 0 and take 4 characters. And IFS is the Internal Field Separator. It controls how words get split. But I didn't see it in the code you posted.
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