_REENTRANT documentation could be better
Several man pages make reference to -D_REENTRANT, but several of the key ones (including Intro(3), perror(3C), and threads(5)) just say to use the "-mt" compiler option. That's a Studio compiler option, while most illumos users today are using gcc (or potentially clang). The pthread_create man page even #define's _REENTRANT directly in the source, before including pthread.h. It would be better if all these man pages included or pointed to a procedure that works for these other compilers.
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