Is the C++ standard library thread safe?

Question

Possible Duplicate:
Do I need to protect read access to an STL container in a multithreading environment?

I am using the C++ standard library which comes with (Linux) GCC or (Windows) VC.

Can anyone please say clearly whether or not this library is thread safe?

It isn't. Unless stated otherwise. You can find all of that in documentation like http://cppreference.com or the [standard specification](http://www.open-std.org/jtc1/sc22/wg21/) — sehe, Jan 02 '13 at 13:12
http://kera.name/articles/2010/08/it-is-not-called-the-stl-mmkay/ — Griwes, Jan 02 '13 at 13:14

wilx · Answer 1 · 2022-02-10T10:05:31.857

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See this video from Herb Sutter: https://web.archive.org/web/20170119232617/https://channel9.msdn.com/posts/C-and-Beyond-2012-Herb-Sutter-You-dont-know-blank-and-blank

edited Feb 10 '22 at 10:05

answered Jan 02 '13 at 13:13

wilx

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well worth the watch. This is such a good backgrounder on this topic. Much more than the title suggests – sehe Jan 03 '13 at 03:51
Great link! Very neat discovery. – Homer6 Jan 24 '14 at 07:45
The video link doesn't work as of 2022. – Dr Phil Feb 09 '22 at 23:31
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@DrPhil Fixed with archive link. – wilx Feb 10 '22 at 10:05

Steve Jessop · Answer 2 · 2013-01-02T13:19:07.403

"Thread safe" is not a clearly-defined boolean property of a library. Some things can be done concurrently and others cannot.

Almost certainly if you were to ask a more detailed question specifying what it is you want to do, the answer would be "no, it is not thread-safe". But only almost.

If by "thread-safe" you mean something like the difference between Vector and ArrayList in Java, then C++ standard containers are non-thread-safe.

Is the C++ standard library thread safe?

2 Answers2