if x > 5; then echo "true"; fi
or
foo > /dev/null 2>1
if (( x > 5 )); then echo "true"; fi
or
foo > /dev/null 2>&1
You are redirecting to or from a filename that is an integer. For example, ls > file
where file
happens to be 3
.
This is not likely to be intentional. The most common causes are:
x > 5
. This should instead be [ "$x" -gt 5 ]
or (( x > 5 ))
.grep -c foo file > 100
instead of [ "$(grep -c foo file)" -gt 100 ]
1>2
instead of 1>&2
.If you do want to create a file named 4
, you can quote it to silence shellcheck and make it more clear to humans that it's not supposed to be taken numerically.
If you use the &>
form of redirection, as in foo > /dev/null 2&>1
, it will trigger this warning. You can safely ignore this warning if that is what triggered it, or change your redirection operator to the semantically preferable >&
.
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.