Additions and clarifications to tutorial 1. #1107
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doc/tut1.txt
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I think it should be mentioned that referential data types, such as sequences, need to be initialized manually.
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Now .add and .len accept nil don't they? So this isn't really necessary for sequences anymore. But it is probably a good idea to put a warning: "Reference types will be nil at the start of the procedure, and thus may require manual initialization."
And other small fixes.
Araq
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Additions and clarifications to tutorial 1.
Clyybber
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## Summary Previously, `osproc` would attempt to allocate memory during fork-exec via the use of `findExe` to find programs in `PATH` . This causes memory allocation during this sensitive period. This PR replaces the use of `findExe` , which was employed due to `execvpe` not being ubiquitous, with `execvpe` , now that it is widely available. ## Details There are a couple problems with allocating memory during fork-exec: - This is extremely unsafe as this code is also used in `vfork()` case (although disabled by default, thankfully), of which the use of an allocator would completely mess up the parent process. - This is super slow, since `fork()` has to perform CoW on pages that are touched by the allocation procedure. - A deadlock can occur in rare cases due to interaction with the global allocator lock. This problem was observed in disruptek/balls. With regard to substituting `findExe` with `execvpe`: * This API has been available in uClibc since 2013, musl libc since 2014 and Haiku since 2015, removing the need to special case against those systems. * We can expect behaviors closer to how other programs perform `PATH` searches. It is expected that there won't be any regression from this change.
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