Editing File descriptor (section)

===Operations on the file descriptor table===
The {{mono|fcntl()}} function is used to perform various operations on a file descriptor, depending on the command argument passed to it. There are commands to get and set attributes associated with a file descriptor, including {{mono|F_GETFD, F_SETFD, F_GETFL}} and {{mono|F_SETFL}}.

*{{mono|[[close (system call)|close()]]}}
*{{mono|closefrom()}} (BSD and Solaris only; deletes all file descriptors greater than or equal to specified number)
*{{mono|close_range()}} (for Linux)<ref>{{cite web |url=https://man7.org/linux/man-pages/man2/close_range.2.html |title=close_range(2) — Linux manual page |author=Stephen Kitt, Michael Kerrisk |access-date=2021-03-22 }}</ref>
*{{mono|[[dup (system call)|dup()]]}} (duplicates an existing file descriptor guaranteeing to be the lowest number available file descriptor)
*{{mono|[[dup2]]()}}, {{mono|[[Dup2|dup3()]]}} (Close fd1 if necessary, and make file descriptor fd1 point to the open file of fd2)
*{{mono|fcntl (F_DUPFD)}}