SC2188
Joachim Ansorg edited this page Nov 12, 2021
·
2 revisions
This redirection doesn't have a command. Move to its command (or use true as no-op).
Problematic code:
{
echo "Report for $(date +%F)"
uptime
df -h
}
> report.txtCorrect code:
{
echo "Report for $(date +%F)"
uptime
df -h
} > report.txtRationale:
ShellCheck found a redirection that doesn't actually redirect from/to anything.
This could indicate a bug, such as in the problematic code where an additional linefeed causes report.txt to be truncated instead of containing report output, or in foo & > bar, where either foo &> bar or foo > bar & was intended.
However, it could also be intentionally used to truncate a file or check that it's readable. You can make this more explicit for both ShellCheck and human readers by using true or : as a dummy command, e.g. true > file or : > file.
Exceptions:
There are no semantic problems with using > foo over true > foo, so if you don't see this as a potential source of bugs or confusion, you can ignore it.