![\"horseshoe](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2019\/06\/horseshoe-bend-1908283_1280.jpg\")
<\/p>\nWhen you interact with the outside world, the iostream library is the way to go in C++. As always, you have to keep a few rules in mind. Let me show which rules.<\/p>\n
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The C++ core guidelines give a good overview of iostreams: Surprisingly for me, and in contrast to the fact, that iostreams are quite essential and are used by most C++ developers, there are only five rules which deal with them, and these rules do have not much content. Here are they:<\/p>\n I have to add additional information to make a story out of the rules. This is not necessary for the first rule:<\/p>\n First, here is a bad example from the guidelines. Using character-level input for more than one character:<\/p>\n <\/p>\n <\/p>\n This is a terrible solution for a simple job. My remark does not hold for the right way to do it:<\/p>\n <\/p>\n \"iostream<\/em><\/code>s is a type safe, extensible, formatted and unformatted I\/O library for streaming I\/O. It supports multiple (and user extensible) buffering strategies and multiple locales. It can be used for conventional I\/O, reading and writing to memory (string streams), and <\/em>user-defines extensions, such as streaming across networks (asio: not yet standardized).<\/em>“<\/p>\n\n
printf<\/code>-family functions call ios_base::sync_with_stdio(false)<\/code><\/a><\/li>\nendl<\/code><\/a><\/li>\n<\/ul>\nSL.io.1: Use character-level input only when you have to<\/a><\/h2>\n
\nchar<\/span> c;\r\nchar<\/span> buf[128<\/span>];\r\nint<\/span> i =<\/span> 0<\/span>;\r\nwhile<\/span> (cin.get(c) &&<\/span> !<\/span>isspace(c) &&<\/span> i <<\/span> 128<\/span>)\r\n buf[i++<\/span>] =<\/span> c;\r\nif<\/span> (i ==<\/span> 128<\/span>) {\r\n \/\/ ... handle too long string ....<\/span>\r\n}\r\n<\/pre>\n<\/div>\n
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