perl 清空缓冲区数据（强制输出缓冲区数据）

[perl]代码库

#-----------------------------
$old_fh = select(OUTPUT_HANDLE);
$| = 1;
select($old_fh);
#-----------------------------
use IO::Handle;
OUTPUT_HANDLE->autoflush(1);
#-----------------------------
# download the following standalone program
#!/usr/bin/perl -w
# seeme - demo stdio output buffering
$| = (@ARGV > 0);      # command buffered if arguments given
print "Now you don't see it...";
sleep 2;
print "now you do\n";

#-----------------------------
    select((select(OUTPUT_HANDLE), $| = 1)[0]);
#-----------------------------
use FileHandle;

STDERR->autoflush;          # already unbuffered in stdio
$filehandle->autoflush(0);
#-----------------------------
use IO::Handle;
# assume REMOTE_CONN is an interactive socket handle,
# but DISK_FILE is a handle to a regular file.
autoflush REMOTE_CONN  1;           # unbuffer for clarity
autoflush DISK_FILE    0;           # buffer this for speed
#-----------------------------
# download the following standalone program
#!/usr/bin/perl
# getpcomidx - fetch www.perl.com's index.html document
use IO::Socket;
$sock = new IO::Socket::INET (PeerAddr => 'www.perl.com',
                              PeerPort => 'http(80)');
die "Couldn't create socket: $@" unless $sock;
# the library doesn't support $! setting; it uses $@

$sock->autoflush(1);

# Mac *must* have \015\012\015\012 instead of \n\n here.
# It's a good idea for others, too, as that's the spec,
# but implementations are encouraged to accept "\cJ\cJ" too,
# and as far as we're seen, they do.
$sock->print("GET /index.html http/1.1\n\n");
$document = join('', $sock->getlines());
print "DOC IS: $document\n";

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