Piping the output of ps through anything seems to cause
strange line truncations.

For example, if ps aux returns line that are longer than 80
characters, piping it through anything causes each line to
be truncated.

ps aux | cat

Every line of output is truncated to 80 characters.

Or:

ps aux | grep "something"

Again, same line truncation.

Also happens with:

ps aux > tmp.txt

Every line of tmp.txt is trucated.