#uuoc spotted !

Ne le provoque pas tonton, sinon il va vouloir se venger.

Guilty as charged.

Note that these commands are subtly different if "foo" does not exist.

$ wc < foo
dash: 1: cannot open foo: No such file
$ echo $?
2
$ cat foo | wc 
cat: foo: No such file or directory
      0       0       0
$ echo $?
0
$ 

#fourbitude

@utzer
Yes. The second line is equivalent to:

wc < /dev/null

In the first line, wc is not even run.

When you have a pipe, like

aaa | bbb | ccc

its exit code will be the exit code of the last command (here "ccc"). You have no way to know if "aaa" or "bbb" failed and returned a non-zero code.