B_NO_MORE_THREADS

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
version(!CRuntime_Microsoft && !CRuntime_Newlib && !linux && !Darwin && !FreeBSD && !NetBSD && !OpenBSD && !DragonFlyBSD && !Solaris && Haiku)
extern (C) @trusted nothrow @nogc
enum B_NO_MORE_THREADS = (B_OS_ERROR_BASE + 0x101);

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