ref: 65e0e1c3e37c966d0c18178ad8a4c54c0c0fbce9
dir: /sys/src/ape/lib/ap/plan9/dup.c/
#include "lib.h" #include <unistd.h> #include <errno.h> int dup(int oldd) { return fcntl(oldd, F_DUPFD, 0); } int dup2(int oldd, int newd) { if(newd < 0 || newd >= OPEN_MAX){ errno = EBADF; return -1; } if(oldd == newd && _fdinfo[newd].flags&FD_ISOPEN) return newd; close(newd); return fcntl(oldd, F_DUPFD, newd); }