Re: [PATCH 1/2] util: Introduce set_cloexec()

On Tue, 6 Jun 2023 13:41:29 +0200 Michal Privoznik wrote:

This function is going to be used on FDs inherited from parent. Parent can't set O_CLOEXEC obviously, so we have to set it ourselves.

Signed-off-by: Michal Privoznik --- util.c | 17 +++++++++++++++++ util.h | 1 + 2 files changed, 18 insertions(+)

diff --git a/util.c b/util.c index 1d00404..9817c74 100644 --- a/util.c +++ b/util.c @@ -526,6 +526,23 @@ int write_file(const char *path, const char *buf) return len == 0 ? 0 : -1; }

+/** + * set_cloexec() - Set Close-on-exec flag on given FD + * @fd: FD to set the flag on

Nits: "close-on-exec", "file descriptor".

+ * + * Return: 0 on success, -1 on any error

I'd rather return errno as set by fcntl(), for consistency.

+ */ +int set_cloexec(int fd) +{ + int fflags; + if ((fflags = fcntl(fd, F_GETFD)) < 0) + return -1; + fflags |= FD_CLOEXEC; + if ((fcntl(fd, F_SETFD, fflags)) < 0) + return -1; + return 0; +}

...but in general, I'm not convinced this is really needed. O_CLOEXEC has been the only file _descriptor_ flag for 16 years, and I have some doubts another one will ever come up (and at that point, we wouldn't probably want to have it set by default anyway). I'd just set it with a direct call. This is not a strong preference though. -- Stefano