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Read command not working as expected

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# 1  
Old 02-26-2012
Read command not working as expected
I was trying to write a simple script which will read a text file and count the number of vowels in the file. My code is given below -
Code:

#!/bin/bash
file=$1
v=0

if [ $# -ne 1 ]
  then
    echo "$0 filename"
    exit 1
fi

if [ ! -f $file ]
  then
    echo "$file not a file"
    exit 2
fi

while read -n 1 c
do
  l=$(echo $c | tr [:upper:] [:lower:])
  [[ "$l" == "a" || "$l" == "e" || "$l" == "i" || "$l" == "o" || "$l" == "u" ]] && (( v++ ))
done < $file

echo "Vowels : $v"

When I run the script, getting the following error -
read: 22: Illegal option -n
However the command read -n 1 c is working fine if I run it from terminal.
Any suggestion is appreciated.
Thanks in advance.
Last edited by jim mcnamara; 02-26-2012 at 11:38 PM.. Reason: please use code tags, not bold tags
# 2  
Old 02-26-2012
I cut and pasted your code and it works fine for me (reading with -n 1). Is it possible that the version of bash that is being invoked isn't the same one executed as your login shell?

You could try something like this that doesn't depend on reading character by character:


Code:
while read buf
do
    vbuf="${buf//[^aeiouAEIOU]/}"
    v=$(( v + ${#vbuf} ))
done <$file
echo "$v vowels"



This works in both bash and Kshell.
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linux_learner
# 3  
Old 02-27-2012
A similar method - use "tr" to delete everything except the vowels and count the result.
Code:
file="$1"
vowels=$(fold -w 1 "${file}" | tr -cd 'aeiouAEIOU' | wc -c)
echo "Vowels : ${vowels}"

Last edited by methyl; 02-27-2012 at 12:58 PM.. Reason: correction suggested by alister
# 4  
Old 02-27-2012
Can try this too...
Code:
# egrep -io "a|e|i|o|u"  $1 | wc -w

eg.
Code:
[root@nagios Shirish@Shukla]# cat my
aa b c d e f g h i j k l m n o p q r s t u v w x y z
[root@nagios Shirish@Shukla]# cat test.sh
echo "Vovels: "`egrep -io "a|e|i|o|u" $1 | wc -w`
[root@nagios Shirish@Shukla]# sh test.sh my
Vovels: 6

--Shirish Shukla
Last edited by Shirishlnx; 02-27-2012 at 11:33 AM..
This User Gave Thanks to Shirishlnx For This Post:
linux_learner
# 5  
Old 02-27-2012
Quote:
Originally Posted by methyl
A similar method - use "tr" to delete everything except the vowels and count the result.
Code:
file="$1"
vowels=$(fold -w 1 "${file}" | tr -cd 'aeiouAeiou' | wc -c)
echo "Vowels : ${vowels}"

I don't see the need for fold since the complemented tr set will delete non-vowels anyway (including newlines). Also, it looks like your finger slipped off the capslock. Smilie

Code:
tr -cd aeiouAEIOU < "$file" | wc -c

Regards,
Alister
These 2 Users Gave Thanks to alister For This Post:
linux_learner methyl
# 6  
Old 02-27-2012
Thanks everyone for your suggestion. But my focus was to run the script, not the algorithm to count the vowels. Sorry for misguiding you.
My problem is that whenever I am trying to run any script from terminal, getting unusual errors like no such commands or invalid option with the command or syntax error etc. But the same commands are working from the terminal separately.
Do I need any settings to run the script? In the script, I am using bash shell, and the same for terminal. If anyone has any suggestion, please let me know.
Thanks in advance.
# 7  
Old 02-27-2012
Just on the off chance, it's not the same problem as before is it?
https://www.unix.com/shell-programmin...-terminal.html

Please post the output from this command which is designed to make control characters visible:
Code:
sed -n l scripname

A normal end-of-line character shows as a dollar sign.
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linux_learner
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