27 lines
1.4 KiB
Text
27 lines
1.4 KiB
Text
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Bionic is a very small C library because we have decided to *not* implement various features
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of the POSIX standard. we only add functions on a as-needed basis, and there are a few things
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we wish we'll never put in there.
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this file is here to document explicitely what we don't want to support in Bionic:
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- C++ exceptions are not supported. on embedded systems, they lead to extremely larger and
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slower code for no good reason (even when so-called zero-cost exception schemes are
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implemented, they enforce very large numbers of registers spills to the stack, even
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in functions that do not throw an exception themselves).
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- pthread cancellation is *not* supported. this seemingly simple "feature" is the source
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of much bloat and complexity in a C library. Besides, you'd better write correct
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multi-threaded code instead of relying on this stuff.
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- pthread_once() doesn't support C++ exceptions thrown from the init function, or the init
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function doing a fork().
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- locales and wide characters are not supported. we use ICU for all this i18n stuff, which
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is much better than the ill-designed related C libraries functions.
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- at the moment, several user-account-related functions like getpwd are stubbed and return
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the values corresponding to root. this will be fixed when we'll be able to have distinct
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users on the Android filesystem. :-(
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see bionic/stubs.c for the details
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