perlfunc
gods
<P>
close - close file (or pipe or socket) handle
<P>
<HR>
<P>
close
<FONT SIZE=-1>FILEHANDLE</FONT>
<P>
close
<P>
<HR>
<P>
Closes the file or pipe associated with the file handle, returning
<FONT SIZE=-1>TRUE</FONT> only if stdio successfully flushes buffers and
closes the system file descriptor. Closes the currently selected filehandle
if the argument is omitted.
<P>
You don't have to close
<FONT SIZE=-1>FILEHANDLE</FONT> if you are immediately going to do another [perlfunc:open|open()] on it, because [perlfunc:open|open()] will close it for you. (See
[perlfunc:open|open()].) However, an explicit [perlfunc:close|close()] on an input file resets the line counter (<CODE>$.</CODE>), while the implicit close done by [perlfunc:open|open()] does not.
<P>
If the file handle came from a piped open [perlfunc:close|close()] will additionally return
<FONT SIZE=-1>FALSE</FONT> if one of the other system calls involved fails
or if the program exits with non-zero status. (If the only problem was that
the program exited non-zero <CODE>$!</CODE> will be set to <CODE>0</CODE>.) Also, closing a pipe waits for the process executing on the pipe to
complete, in case you want to look at the output of the pipe afterwards.
Closing a pipe explicitly also puts the exit status value of the command
into <CODE>$?</CODE>.
<P>
Example:
<P>
<PRE> open(OUTPUT, '|sort >foo') # pipe to sort
or die "Can't start sort: $!";
#... # print stuff to output
close OUTPUT # wait for sort to finish
or warn $! ? "Error closing sort pipe: $!"
: "Exit status $? from sort";
open(INPUT, 'foo') # get sort's results
or die "Can't open 'foo' for input: $!";
</PRE>
<P>
<FONT SIZE=-1>FILEHANDLE</FONT> may be an expression whose value can be
used as an indirect filehandle, usually the real filehandle name.
<HR>