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How to read a text file and assign the values in the same to a variable in loop


 
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# 8  
Old 06-09-2011
Quote:
Originally Posted by gary_w
Code:
#!/bin/ksh
...
while IFS=',' read path age
do
    ...
done < $file

Definitely the cleanest, most efficient way to handle this scenario.

Just in case a novice thinks they need ksh to run that, /bin/sh should do just fine.

Regards,
Alister
# 9  
Old 06-09-2011
Thank you

But for /bin/sh one would need to change the "print" command to "echo" but the main logic will still work. For the sake of the novices, "print" is built-in to ksh and this runs faster where "echo" is actually another program that must be called and thus brings along some overhead.

My normal shell is ksh93 on Solaris so that's how my brain thinks these days. :-)
# 10  
Old 06-09-2011
Hi, gary_w:

You are absolutely correct about print. I overlooked it.

However, you are mistaken about echo. It is actually built into ksh93. At least, it is into the one I just tested.

Even so, I'm not a big fan of echo myself. I much prefer the portability and safety of printf.

Regards,
Alister
# 11  
Old 06-09-2011
Interesting

Code:
$ echo $SHELL
/usr/dt/bin/dtksh
$ which echo
/bin/echo
$ ksh
$ which echo
/bin/echo
$

echo seems to be a separate program on our Solaris box, but I believe we are not on the latest version anyway. Just goes to show you not to assume anything and know that things may work differently then expected depending on the OS version and shell version you are using!
# 12  
Old 06-09-2011
Quote:
Originally Posted by gary_w
echo seems to be a separate program on our Solaris box
Just having an external echo doesn't mean your shell actually uses it. There's supposed to be back-up externals for any shell internal.

That's often taken literally to an extreme, to the point some vendors supply an external cd program. Think about that for a minute. What would an external cd program do in your shell.
# 13  
Old 06-09-2011
Yeah look at this

Code:
$ command -V echo
echo is a shell builtin
$ command -V print
print is a shell builtin
$ which echo
/bin/echo
$ which print
no print in /opt/oracle/10.2.0/bin /opt/oracle/10.2.0/bin /sbin /usr/sbin /etc /usr/ccs/bin /usr/openwin/bin 
/usr/dt/bin /bin /usr/bin /usr/ucb /etc /home/efs/bin . 
$

So it seems echo is indeed built-in and external where print is only built-in.

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