close.2 (2010 09)

c
close(2) close(2)
NAME
close - close a file descriptor
SYNOPSIS
#include <unistd.h>
int close(int fildes);
DESCRIPTION
close() closes the file descriptor indicated by fildes. fildes is a file descriptor obtained from a
creat(), open(), dup(), fcntl()
,or pipe() system call. All associated file segments which have
been locked by this process with the
lockf() function are released (i.e., unlocked).
RETURN VALUE
Upon successful completion,
close() returns a value of 0; otherwise, it returns − 1 and sets
errno to
indicate the error.
ERRORS
close() fails if the any of following conditions are encountered:
[EBADF] fildes is not a valid open file descriptor.
[EINTR] An attempt to close a slow device or connection or file with pending aio requests was
interrupted by a signal. The file descriptor still points to an open device or connec-
tion or file.
[ENOSPC] Not enough space on the file system. This error can occur when closing a file on an
NFS file system. [When a write() system call is executed on a local file system
and if a new buffer needs to be allocated to hold the data, the buffer is mapped onto
the disk at that time. A full disk is detected at this time and write() returns an
error. When the write() system call is executed on an NFS file system, the new
buffer is allocated without communicating with the
NFS server to see if there is
space for the buffer (to improve
NFS performance). It is only when the buffer is
written to the server (at file close or the buffer is full) that the disk-full condition is
detected.]
SEE ALSO
creat(2), dup(2), exec(2), fcntl(2), lockf(2), open(2), pipe(2), thread_safety(5).
STANDARDS CONFORMANCE
close(): AES, SVID2, SVID3, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1