c - %[^<] (和 friend )在格式化字符串系列中是什么意思？

Question

A comment (可能应该作为答案提交)有代码

sscanf(string, "<title>%[^<]</title>", extracted_string);

运行代码似乎复制了 <title> 之间的文本标记为 extracted_string , 但我在 man pages 中找不到任何对 printf 系列插入符号的引用或 elsewhere online .

谁能给我指出解释 %[^<] 用法的资源？ ，和其他类似的语法，在 sscanf()家人？

Answer 1

来自 C11 标准文档，章节 §7.21.6.2，第 12 段，转换说明符，(强调我的)

[

Matches a nonempty sequence of characters from a set of expected characters (the scanset).

....

The conversion specifier includes all subsequent characters in the format string, up to and including the matching right bracket (]). The characters between the brackets (the scanlist) compose the scanset, unless the character after the left bracket is a circumflex (^), in which case the scanset contains all characters that do not appear in the scanlist between the circumflex and the right bracket.

A draft version of the standard, found online .