01-28-2016
Quote:
Originally Posted by
Don Cragun
Shells are not known for their ability to opens hundreds of files. Certainly, you could write for loops nested to hundreds of levels with input for each loop redirected (and, therefore, each loop eating up an additional file descriptor) and your shell might or might not be willing to accept and run that script.
If you want to open hundreds of file descriptors just to keep them open and do nothing with them, it would be much easier to do it in C than in shell.
thanks reply,
yes , what I would like to do is eating up an additional file descriptor , would advsie a simple script to do that ?
thanks
---------- Post updated at 12:29 PM ---------- Previous update was at 10:35 AM ----------
I just would like have a script to repeatly eating up open files , so that make it increase to a certain level
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LEARN ABOUT FREEBSD
stderr
FD(4) BSD Kernel Interfaces Manual FD(4)
NAME
fd, stdin, stdout, stderr -- file descriptor files
DESCRIPTION
The files /dev/fd/0 through /dev/fd/# refer to file descriptors which can be accessed through the file system. If the file descriptor is
open and the mode the file is being opened with is a subset of the mode of the existing descriptor, the call:
fd = open("/dev/fd/0", mode);
and the call:
fd = fcntl(0, F_DUPFD, 0);
are equivalent.
Opening the files /dev/stdin, /dev/stdout and /dev/stderr is equivalent to the following calls:
fd = fcntl(STDIN_FILENO, F_DUPFD, 0);
fd = fcntl(STDOUT_FILENO, F_DUPFD, 0);
fd = fcntl(STDERR_FILENO, F_DUPFD, 0);
Flags to the open(2) call other than O_RDONLY, O_WRONLY and O_RDWR are ignored.
IMPLEMENTATION NOTES
By default, /dev/fd is provided by devfs(5), which provides nodes for the first three file descriptors. Some sites may require nodes for
additional file descriptors; these can be made available by mounting fdescfs(5) on /dev/fd.
FILES
/dev/fd/#
/dev/stdin
/dev/stdout
/dev/stderr
SEE ALSO
tty(4), devfs(5), fdescfs(5)
BSD
June 9, 1993 BSD