SC1012

\t is just literal t here. For tab, use "$(printf '\t')" instead.

Problematic code:

# Want tab
$ var=foo\tbar
$ printf '<%s>\n' "$var"
<footbar>

or

# Want linefeed
$ var=foo\nbar
$ printf '<%s>\n' "$var"
<foonbar>

Correct code:

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

or

# Literal, quoted linefeed
$ line="foo
> bar"
$ printf '<%s>\n' "$line"
<foo
bar>

or

# Linefeed using ANSI-C quoting
$ line=$'foo\nbar'
$ printf '<%s>\n' "$line"
<foo
bar>

Rationale:

ShellCheck has found a \t, \n or \r in a context where they just become regular letters 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.

Exceptions:

None.

Related resources:

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