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0 pointsadrian_b1y ago0 comments

POSIX does not require malloc to be signal safe.

Therefore I do not think that anyone has bothered to implement a signal-safe malloc, as this is likely to be complicated.

Allocating memory in a signal handler makes no sense in a well designed program, so not being allowed to use malloc and related functions is not a problem.

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skissane1y ago

On Linux, mmap() is your signal-safe malloc.

POSIX doesn't require mmap() to be async-signal safe, but on Linux it de facto is.

Of course, doing every memory allocation at the kernel level is going to be very slow and resource intensive. But if it isn't on a hot code path...

tedunangst1y ago

So it sounds like malloc would be an example of a function which is thread safe but not reentrant.

j / k navigate · click thread line to collapse