There are two formats for redirecting standard output and standard error:
&>word
and
>&word
Of the two forms, the first is preferred. This is semantically equivalent to
>word 2>&1
When using the second form, word may not expand to a number or ‘-’. If it does, other redirection operators apply (see Duplicating File Descriptors below) for compatibility reasons.
cmd > file.log 2>error.log
А если нужно сделать так, что если a>1 мы едим черта, а если меньше, мы рисуем кружочек?