2 SC1012

John Gardner edited this page 2021-12-22 18:34:38 +11:00

Table of Contents

• \t is just literal t here. For tab, use "$(printf '\t')" instead.
• Problematic code:
• Correct code:
• Rationale:
• Exceptions:
• Related resources:

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

Problematic code:

# Want tab
var=foo\tbar

or

# Want linefeed
var=foo\nbar

Correct code:

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

or

# Literal, quoted linefeed
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:

• Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!

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