I'd like to send a process:Command to a new thread, but that does not work, because on Unix, the Command struct has a raw pointer field: pub struct Command { // Currently we try hard to ensure that the call to `.exec()` doesn't // actually allocate any memory. While many platforms try to en…

argv is defined that way because it's the type of array that libc::execvp needs. But it's pointing to the memory owned by args, so we could probably just manually implement Send and Sync anyway.

I think the problem here is that argv must be terminated by a null pointer.

Yeah but a CString is nul-terminated too.

Yeah, filing an issue would be good. I think it will mostly be a question of whether the libs team wants to commit to Command being Send + Sync forever. But it effectively must be so anyway, since it is used across a fork. [image] little_dude: Yeah but a CString is nul-terminated too. The …

The problem is not the raw strings, but that the list of pointers must have a 0 pointer at the end. (see http://pages.cs.wisc.edu/~smoler/cs354/onyourown/C.argv.html , search for "ANSI standard") I'd recommend going @cuviper 's round and would open an issue asking for a Send bound.

I ended up opening an issue and a PR to implement Send for Command. My first unsafe piece of code, and it's now part of the standard library! :tada: Thanks a lot!

Would it be possible for std::process::Command to be Send?

help

little_dude January 25, 2018, 7:57pm 4

Should I open an issue on rust-lang/rust?

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Would it be possible for std::process::Command to be Send?

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