# Want tab
var=foo\tbar

or

# Want linefeed
var=foo\nbar

var="foo$(printf '\t')bar"  # As suggested in warning
var="$(printf 'foo\tbar')"  # Equivalent alternative

or

# Literal, quoted linefeed
line="foo
bar"

ShellCheck has found a \t, \n or \r in a context where they just become regular letter t, n or r. Most likely, it was intended as a tab, linefeed or carriage return.

To generate such characters (plus other less common ones including \a, \f and octal escapes) , use printf as in the example. The exception is for linefeeds that would be stripped by command substitution; in these cases, use a literal quoted linefeed instead.

Other characters like \z generate a SC1001 info message, as the intent is less certain.

None.

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