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# 1  
Old 10-10-2007
Tail Question

Hi All,

I notice that the below tail cannot be done.
How can i modify this code such that i can always "tail" a variable number of lines ?

Code:
set num = 100
cat filename|grep xxx| tail -$num

# 2  
Old 10-10-2007
try:
Code:
tail -n $num somefile

# 3  
Old 10-10-2007
"set" with spaces might not work .... just use the below:

num=100
cat filename|grep xxx| tail -$num


Paste below in a file called "q"

#!/bin/ksh
num=$1
cat filename|grep xxx| tail -$num


filename contains:
xxxxxx
xxxxxx
asfasfa
xxxx


so when I run
$>q 2
It gives
xxxxxx
xxxx


Hope this helps,
V
# 4  
Old 10-11-2007
Hi mvijayv,

I am using csh by the way.

Hi jim mcnamara,

Looks like i can run using the below

Code:
/usr/xpg4/bin/tail -n $num somefile

but can anybody tell me what's the difference between
/usr/xpg4/bin/tail
and
/usr/bin/tail ?
# 5  
Old 10-11-2007
The /usr/xpg4/bin/tail is a tail that confirms to the XPG4 standard (link). The /usr/bin/tail may not necessarily confirm to that.
# 6  
Old 11-28-2007
Hi ,

Does this /usr/xpg4/bin/head -n $num exist ?

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