#include #include "namespace.h" #include #include #include #ifdef __weak_alias __weak_alias(dup2, _dup2) #endif int dup2(fd, fd2) int fd, fd2; { /* The behavior of dup2 is defined by POSIX in 6.2.1.2 as almost, but not * quite the same as fcntl. */ if (fd2 < 0 || fd2 > OPEN_MAX) { errno = EBADF; return(-1); } /* Check to see if fildes is valid. */ if (fcntl(fd, F_GETFL) < 0) { /* 'fd' is not valid. */ return(-1); } else { /* 'fd' is valid. */ if (fd == fd2) return(fd2); close(fd2); return(fcntl(fd, F_DUPFD, fd2)); } }