tag 20954 + notabug
close 20954
thanks
tele wrote:
Hi!
Hi!
From terminal:
$ a="" ; echo $s | wc -l
1
Do you mean $a instead of $s? Either way is the same though assuming
$s is empty too.
- Yes, my mistake :-)
Should be 0 , yes ?
No. Should be 1. You have forgotten about the newline at the end of
the command. The echo will terminate with a newline. You can see
this with od.
echo | od -tx1 -c
0000000 0a
\n
Since this appears to be a usage error I have closed the bug. Please
feel free to follow up with more information. We will read it. And
we appreciate additional communication! I am simply closing it to
keep the accounting straight.
Bob
# "echo" gives in new line, "echo -n" subtracts 1 line, but "wc -l" can count
only from new line,
# so if something exist inside first line "wc -l" can not count. :-(
# example:
#
# $ a="j" ; echo "$a" | wc -l
# 1
#
# $ a="" ; echo "$a" | wc -l
# 1
#
# $ a="" ; echo -n "$a" | wc -l
# 0
#
# $ a="j" ; echo -n "$a" | wc -l
# 0
So,
$ a="" ; echo "$a" | sed '/^\s*$/d' | wc -l
0
$ a="3" ; echo "$a" | sed '/^\s*$/d' | wc -l
1
Can be added option to "wc" to fix this problem without use sed in future ?
Thanks for helping :-)
