get just the integer from wc in bash

问题

Is there a way to get the integer that wc returns in bash?

Basically I want to write the line numbers and word counts to the screen after the file name.

output: filename linecount wordcount Here is what I have so far:

files=`ls`
for f in $files;
do
        if [ ! -d $f ] #only print out information about files !directories
        then
                # some way of getting the wc integers into shell variables and then printing them
                echo "$f $lines $ words"
        fi
done

回答1:

You can use the cut command to get just the first word of wc's output (which is the line or word count):

lines=`wc -l $f | cut -f1 -d' '`
words=`wc -w $f | cut -f1 -d' '`

回答2:

Most simple answer ever:

wc < filename

回答3:

Just:

wc -l < file_name

will do the job. But this output includes prefixed whitespace as wc right-aligns the number.

回答4:

wc $file | awk {'print "$4" "$2" "$1"'}

Adjust as necessary for your layout.

It's also nicer to use positive logic ("is a file") over negative ("not a directory")

[ -f $file ] && wc $file | awk {'print "$4" "$2" "$1"'}

回答5:

Sometimes wc outputs in different formats in different platforms. For example:

In OS X:

$ echo aa | wc -l

         1

In Centos:

$ echo aa | wc -l

1

So using only cut may not retrieve the number. Instead try tr to delete space characters:

$ echo aa | wc -l | tr -d ' '

回答6:

The accepted/popular answers do not work on OSX.

Any of the following should be portable on bsd and linux.

wc -l < "$f" | tr -d ' '

wc -l "$f" | tr -s ' ' | cut -d ' ' -f 2

wc -l "$f" | awk '{print $1}'

回答7:

If you redirect the filename into wc it omits the filename on output.

Bash:

read lines words characters <<< $(wc < filename)

read lines words characters <<EOF
$(wc < filename)
EOF

Instead of using for to iterate over the output of ls, do this:

for f in *

which will work if there are filenames that include spaces.

If you can't use globbing, you should pipe into a while read loop:

find ... | while read -r f

or use process substitution

while read -r f
do
    something
done < <(find ...)

回答8:

If the file is small you can afford calling wc twice, and use something like the following, which avoids piping into an extra process:

lines=$((`wc -l "$f"`))
words=$((`wc -w "$f"`))

The $((...)) is the Arithmetic Expansion of bash. It removes any whitespace from the output of wc in this case.

This solution makes more sense if you need either the linecount or the wordcount.

回答9:

How about with sed?

wc -l /path/to/file.ext | sed 's/ *\([0-9]* \).*/\1/'

回答10:

Try this for numeric result:
nlines=$( wc -l < $myfile )

回答11:

Try this:

wc `ls` | awk '{ LINE += $1; WC += $2 } END { print "lines: " LINE  " words: " WC }'

It creates a line count, and word count (LINE and WC), and increase them with the values extracted from wc (using $1 for the first column's value and $2 for the second) and finally prints the results.

回答12:

typeset -i a=$(wc -l fileName.dat  | xargs echo | cut -d' ' -f1)

回答13:

"Basically I want to write the line numbers and word counts to the screen after the file name."

answer=(`wc $f`)
echo -e"${answer[3]}
lines:  ${answer[0]}
words:  ${answer[1]}
bytes:  ${answer[2]}"

Outputs : myfile.txt lines: 10 words: 20 bytes: 120

回答14:

files=`ls`
echo "$files" | wc -l | perl -pe "s#^\s+##"

回答15:

Another way, similar to what @BananaNeil posted:

$ cat myfile.txt | wc -l

来源：https://stackoverflow.com/questions/3746947/get-just-the-integer-from-wc-in-bash

标签

bash