_PC_PIPE_BUF      848 ext/etc/constdefs.h #if !defined(_PC_PIPE_BUF)
_PC_PIPE_BUF      850 ext/etc/constdefs.h #  define _PC_PIPE_BUF _PC_PIPE_BUF
_PC_PIPE_BUF     1448 ext/etc/constdefs.h #if defined(_PC_PIPE_BUF)
_PC_PIPE_BUF     1449 ext/etc/constdefs.h     rb_define_const(mod, "PC_PIPE_BUF", INTEGER2NUM(_PC_PIPE_BUF));