NAME
       close - close a file descriptor



SYNOPSIS
       #include <unistd.h>

       int close(int fd);



DESCRIPTION
       close  closes  a  file  descriptor,  so  that it no longer
       refers to any file and may be reused.

       If fd is the last copy of a particular file descriptor the
       resources  associated  with  it are freed; for example any
       locks held are removed and if the descriptor was the  last
       reference  to  a  file which has been removed using unlink
       the file is deleted.



RETURN VALUE
       close returns zero on success, or -1 if an error occurred.



ERRORS
       EBADF  fd isn't a valid open file descriptor.



CONFORMING TO
       SVID, AT&T, POSIX, X/OPEN, BSD 4.3



NOTES
       Not  checking  the  return  value of close is a common but
       nevertheless  serious  programming  error.   File   system
       implementations  which  use techniques as ``write-behind''
       to increase performance may lead to  write(2)  succeeding,
       although  the  data  has  not been written yet.  The error
       status may be reported at a later write operation, but  it
       is  guaranteed  to  be  reported on closing the file.  Not
       checking the return value when closing the file  may  lead
       to  silent  loss of data.  This can especially be observed
       with NFS and disk quotas.



SEE ALSO
       open(2), fcntl(2), shutdown(2), unlink(2), fclose(3).