Sum in shell script

Question

Why can't I create a sum of total words in this script? I get the result something like:

 120+130

but it isn't 250 (as I expected)! Is there any reason?

#!/bin/bash

while [ -z "$count" ] ;
do
    echo -e "request :: please enter file name "
    echo -e "\n\tfile one : \c"
    read count

    itself=counter.sh

    countWords=`wc -w $count |cut -d ' ' -f 1`
    countLines=`wc -l $count |cut -d ' ' -f 1`
    countWords_=`wc -w $itself |cut -d ' ' -f 1`

    echo "Number of lines: " $countLines
    echo "Number of words: " $countWords
    echo "Number of words -script: " $countWords_

    echo "Number of words -total " $countWords+$countWords_  

done

if [ ! -e $count ] ; then
    echo -e "error :: file one $count doesn't exist. can't proceed."
    read empty
    exit 1
fi

don't use <br>, use the "code sample (ctrl-K)" button.

J-16 SDiZ
– J-16 SDiZ

2011-01-06 05:19:32 +00:00
Commented Jan 6, 2011 at 5:19 — J-16 SDiZ
– J-16 SDiZ, Commented Jan 6, 2011 at 5:19

SiegeX · Accepted Answer · 2011-01-06 05:48:19Z

6

echo "Number of words -total " $countWords+$countWords_

You want this:

echo "Number of words -total $((countWords + countWords_))"

Edit

Here are some optimizations to your script.

The while loop seems pointless since count is going to get set for sure inside making this a 1-iteration while loop.
Your if check on existence of the file should happen before you ever use that file.
You don't need to hardcode the name of your script to the variable itself, you can use $0 for that
Since you are using bash I took the liberty to remove the need for cut by using process substitution.

Here is the revised script:

#!/bin/bash

echo -e "request :: please enter file name "
echo -e "\n\tfile one : \c"
read count

if [ ! -e "$count" ] ; then
    echo "error :: file one $count doesn't exist. can't proceed."
    exit 1
fi

itself="$0"

read countWords _ < <(wc -w $count)
read countLines _ < <(wc -l $count)
read countWords_ _ < <(wc -w $itself)

echo "Number of lines: '$countLines'"
echo "Number of words: '$countWords'"
echo "Number of words -script: '$countWords_'"

echo "Number of words -total $((countWords + countWords_))"

edited Jan 6, 2011 at 5:48

answered Jan 6, 2011 at 5:17

SiegeX

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1 Comment

Dennis Williamson Over a year ago

countWords=$(wc -w < "$count") will get the count without the file name. Or you could use one call to wc instead of two: read countLines countWords <<< $(wc -lw < "$count"). $count could be null if the user presses enter. This will cause the while loop to continue looping until the user inputs something.

Amir Afghani · Accepted Answer · 2011-01-06 05:17:34Z

1

One way to go about this is:

echo `expr $countWords + $countWords_`

answered Jan 6, 2011 at 5:17

Amir Afghani

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6 Comments

SiegeX Over a year ago

expr has been deprecated, use $(( )) instead

J-16 SDiZ Over a year ago

@SiegeX, $(( )) is bash-syntax, don't break posix bourne shell.

Jonathan Leffler Over a year ago

$(( ... )) is POSIX shell; it is also Korn shell (and Bash); it is not Bourne shell.

SiegeX Over a year ago

@Jonathan thanks for doing my dirty work. This convo seems eerily familiar =)

SiegeX Over a year ago

@J-16 even if $(( )) weren't POSIX syntax, the #!/bin/bash at the top of his script would make this a pretty moot point

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