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close(2) [v7 man page]

CLOSE(2)							System Calls Manual							  CLOSE(2)

NAME
close - close a file SYNOPSIS
close(fildes) DESCRIPTION
Given a file descriptor such as returned from an open, creat, dup or pipe(2) call, close closes the associated file. A close of all files is automatic on exit, but since there is a limit on the number of open files per process, close is necessary for programs which deal with many files. Files are closed upon termination of a process, and certain file descriptors may be closed by exec(2) (see ioctl(2)). SEE ALSO
creat(2), open(2), pipe(2), exec(2), ioctl(2) DIAGNOSTICS
Zero is returned if a file is closed; -1 is returned for an unknown file descriptor. ASSEMBLER
(close = 6.) (file descriptor in r0) sys close CLOSE(2)

Check Out this Related Man Page

CLOSE(2)							System Calls Manual							  CLOSE(2)

NAME
close - delete a descriptor SYNOPSIS
close(d) int d; DESCRIPTION
The close call deletes a descriptor from the per-process object reference table. If this is the last reference to the underlying object, then it will be deactivated. For example, on the last close of a file the current seek pointer associated with the file is lost; on the last close of a socket(2) associated naming information and queued data are discarded; on the last close of a file holding an advisory lock the lock is released (see further flock(2)). A close of all of a process's descriptors is automatic on exit, but since there is a limit on the number of active descriptors per process, close is necessary for programs that deal with many descriptors. When a process forks (see fork(2)), all descriptors for the new child process reference the same objects as they did in the parent before the fork. If a new process is then to be run using execve(2), the process would normally inherit these descriptors. Most of the descrip- tors can be rearranged with dup2(2) or deleted with close before the execve is attempted, but if some of these descriptors will still be needed if the execve fails, it is necessary to arrange for them to be closed if the execve succeeds. For this reason, the call ``fcntl(d, F_SETFD, 1)'' is provided, which arranges that a descriptor will be closed after a successful execve; the call ``fcntl(d, F_SETFD, 0)'' restores the default, which is to not close the descriptor. RETURN VALUE
Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and the global integer variable errno is set to indicate the error. ERRORS
Close will fail if: [EBADF] D is not an active descriptor. SEE ALSO
accept(2), flock(2), open(2), pipe(2), socket(2), socketpair(2), execve(2), fcntl(2) 4th Berkeley Distribution May 22, 1986 CLOSE(2)

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