Implement functionality for duplicating a file descriptor and having the close-on-fork flag automatically set in the new file descriptor. Signed-off-by: Nate Karstens <nate.karstens@xxxxxxxxxx> --- fs/fcntl.c | 4 ++++ include/uapi/linux/fcntl.h | 3 +++ tools/include/uapi/linux/fcntl.h | 3 +++ 3 files changed, 10 insertions(+) diff --git a/fs/fcntl.c b/fs/fcntl.c index 40af2a48702b..e15cdd77b1df 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -333,6 +333,9 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg, case F_DUPFD_CLOEXEC: err = f_dupfd(arg, filp, O_CLOEXEC); break; + case F_DUPFD_CLOFORK: + err = f_dupfd(arg, filp, O_CLOFORK); + break; case F_GETFD: err = f_getfd(fd); break; @@ -437,6 +440,7 @@ static int check_fcntl_cmd(unsigned cmd) switch (cmd) { case F_DUPFD: case F_DUPFD_CLOEXEC: + case F_DUPFD_CLOFORK: case F_GETFD: case F_SETFD: case F_GETFL: diff --git a/include/uapi/linux/fcntl.h b/include/uapi/linux/fcntl.h index ca88b7bce553..9e1069ff3a22 100644 --- a/include/uapi/linux/fcntl.h +++ b/include/uapi/linux/fcntl.h @@ -55,6 +55,9 @@ #define F_GET_FILE_RW_HINT (F_LINUX_SPECIFIC_BASE + 13) #define F_SET_FILE_RW_HINT (F_LINUX_SPECIFIC_BASE + 14) +/* Create a file descriptor with FD_CLOFORK set. */ +#define F_DUPFD_CLOFORK (F_LINUX_SPECIFIC_BASE + 15) + /* * Valid hint values for F_{GET,SET}_RW_HINT. 0 is "not set", or can be * used to clear any hints previously set. diff --git a/tools/include/uapi/linux/fcntl.h b/tools/include/uapi/linux/fcntl.h index ca88b7bce553..9e1069ff3a22 100644 --- a/tools/include/uapi/linux/fcntl.h +++ b/tools/include/uapi/linux/fcntl.h @@ -55,6 +55,9 @@ #define F_GET_FILE_RW_HINT (F_LINUX_SPECIFIC_BASE + 13) #define F_SET_FILE_RW_HINT (F_LINUX_SPECIFIC_BASE + 14) +/* Create a file descriptor with FD_CLOFORK set. */ +#define F_DUPFD_CLOFORK (F_LINUX_SPECIFIC_BASE + 15) + /* * Valid hint values for F_{GET,SET}_RW_HINT. 0 is "not set", or can be * used to clear any hints previously set. -- 2.26.1