config.txt: document behavior of backslashes in subsections

Unrecognized escape sequences are invalid in values: $ git config -f - --list <<EOF [foo] bar = "\t\\\y\"\u" EOF fatal: bad config line 2 in standard input But in subsection names, the backslash is simply dropped if the following character does not produce a recognized escape sequence: $ git config -f - --list <<EOF [foo "\t\\\y\"\u"] bar = baz EOF foo.t\y"u.bar=baz Although it would be nice for subsection names and values to have consistent behavior, changing the behavior for subsection names is a nonstarter since it would cause existing, valid config files to suddenly be interpreted differently. Signed-off-by: Dave Borowitz <dborowitz@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Dave Borowitz committed Dec 21, 2017 at 08:10 UTC 1feb061701463410647665c4848b6466bf7a97c6
1 file changed +7 -5
Documentation/config.txt
+7 -5
@@ -41,11 +41,13 @@ in the section header, like in the example below:
41 --------
42
43 Subsection names are case sensitive and can contain any characters except
44 -newline (doublequote `"` and backslash can be included by escaping them
45 -as `\"` and `\\`, respectively). Section headers cannot span multiple
46 -lines. Variables may belong directly to a section or to a given subsection.
47 -You can have `[section]` if you have `[section "subsection"]`, but you
48 -don't need to.
44 +newline and the null byte. Doublequote `"` and backslash can be included
45 +by escaping them as `\"` and `\\`, respectively. Backslashes preceding
46 +other characters are dropped when reading; for example, `\t` is read as
47 +`t` and `\0` is read as `0` Section headers cannot span multiple lines.
48 +Variables may belong directly to a section or to a given subsection. You
49 +can have `[section]` if you have `[section "subsection"]`, but you don't
50 +need to.
51
52 There is also a deprecated `[section.subsection]` syntax. With this
53 syntax, the subsection name is converted to lower-case and is also