Why wc adds plus one

Question

Lets say I have a word of length N.

word0=`echo` # N = 0  
word1=`echo A` # N = 1
word2=`echo AB` # N = 2
word5=`echo ABCDE` # N = 5
word4=`echo "ABCD"` # N = 4

I use wc to get the length ofwordN, for example:

echo $word0 | wc 
   1 
echo $word1 | wc 
   2 
echo $word4 | wc 
   5

wc adds +1 to the word length and result is N+1

Even with wc -c or wc -m I got N+1

Question: Should wc work like this? If so, why it adds +1?

Those are [useless `echo`s](http://www.iki.fi/era/unix/award.html#echo) though; you want simply `word0=''; word1='A'` etc — tripleee, Aug 25 '21 at 19:24

score 10 · Accepted Answer · answered Nov 05 '13 at 14:22

try:

echo -n "stuff"|wc

echo adds a newline, so if you count by bytes or chars, there is at least 1

see following examples:

kent$  echo ""|wc -c
1

kent$  echo -n ""|wc -c
0

kent$  echo  ""|wc -m
1

kent$  echo  -n ""|wc -m
0

if you count by "word", there is no difference:

kent$  echo  -n ""|wc -w
0

kent$  echo  ""|wc -w   
0

score 2 · Answer 2 · answered Nov 05 '13 at 14:19

2

My wc prints three values: line count, word count and byte count. I guess yours just prints the byte count. And the echo command you use in the pipe always adds a newline. That's the additional byte you are looking for.

answered Nov 05 '13 at 14:19

Alfe

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Ok, so this is `echo` newline fault? – pogibas Nov 05 '13 at 14:20
`word0` contains 0 bytes, but `echo $word0` outputs the empty string followed by a newline. Try `echo -n $word0 | wc`. – chepner Nov 05 '13 at 14:23
1

It's the _reason_, not a _fault_, I would say, yes. – Alfe Nov 05 '13 at 14:23
Or maybe strip that `wc` completely and use `echo ${#word5}` to get the length of the variable value. – Alfe Nov 05 '13 at 14:25

Why wc adds plus one

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