What does _r suffix mean?

Question

I know _r suffix is used to indicate something thread-safe. For example strtok and strtok_r or libmysql.so and libmysql_r.so. But I cannot find anywhere what this actually means ? For example, _t means 'type' and what does _r suffix mean?

score 10 · Accepted Answer · answered Oct 27 '12 at 19:28

10

See Chapter A.4.16 Thread-Safety in http://pubs.opengroup.org/onlinepubs/000095399/xrat/xbd_chap04.html:

The suffix "_r" is historical, where the 'r' stood for "reentrant".

answered Oct 27 '12 at 19:28

halex

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score 5 · Answer 2 · answered Oct 27 '12 at 19:26

5

The _r suffix stands for reentrant.

answered Oct 27 '12 at 19:26

Olaf Dietsche

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score 3 · Answer 3 · answered Oct 27 '12 at 19:28

3

_r means reentrant, even though those functions may not be really reentrant. Those functions just guarantee not to use static storage.

answered Oct 27 '12 at 19:28

ninjalj

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See also the discussion in the comments of http://stackoverflow.com/a/8405940/371250 – ninjalj Oct 27 '12 at 19:29

What does _r suffix mean?

3 Answers3

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