On Thu, Jan 31 2008, Michael Kerrisk wrote: > > > Jens Axboe wrote: > > On Thu, Jan 31 2008, Michael Kerrisk wrote: > >> Hi Cong, > >> > >> WANG Cong wrote: > >>> Hi, Michael and list! > >>> > >>> I found two problems in the man pages. The first one should > >>> be a bug. It is that the type of the 2nd and 4th arguments > >>> of splice(2) is wrong. The current prototype of splice(2) > >>> in current man page is: > >>> > >>> long splice(int fd_in, off_t *off_in, int fd_out, > >>> off_t *off_out, size_t len, unsigned int flags); > >>> > >>> However, they should be 'loff_t' instead of 'off_t'. If we > >>> use 'off_t', gcc will generate a warning. Patch is in the end > >>> of this email and it's against 2.76 release. ;) > >> Thanks for spotting that. Fixed as you suggest, for man-pages-2.77. > >> > >>> The second one is a bit confused. The example given in tee(2) > >>> even can not run normally. I got this error: > >>> > >>> $ ./example bar.txt > >>> tee: Invalid argument > >>> > >>> I looked at tee(2), it is said that: > >>> > >>> EINVAL fd_in or fd_out does not refer to a pipe; or fd_in and fd_out > >>> refer to the same pipe. > >>> > >>> So the first two arguments of tee(2) in the example is wrong, > >>> since neither STDIN_FILENO nor STDOUT_FILENO refers to a pipe. > >>> But I am not so sure, because I am new to tee(2). ;) If you can > >>> comfirm this is really a bug, I can send a patch to fix this too. > >>> > >>> I have checked the newest release of man pages and my kernel version > >>> is 2.6.21-1.3194.fc7. Did I miss something obvious? > >> I'm not sure. Perhaps Jens, the implementer of tee(2) can provide a little > >> help. Jens, what's an example of a command line for running the example > >> program in the tee.2 man page? > > > > It's not a bug, it should be run as: > > > > $ echo hello | ./example output_file | cat > > > > so that both stdin and stdout are pipes, as described in the man page. > > The man page is correct. > > Hi jens, > > Yes, I guessed you probably should run it like that. And it does produce > the expected output on stdout. However, the command then blocks, and if > one types control-C, the output_file is empty. How should this program be > terminated so that something does end up in the output_file? See ktee.c from the splice sample repo, it works correctly: axboe@carl:~/git/splice> echo hello | ./ktee outfile | cat hello axboe@carl:~/git/splice> cat outfile hello I don't have the tee(2) man page here so can't verify, but try and compare them! -- Jens Axboe - To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
