第一章:read/sysread/print/syswrite区别

use strict;
use warnings;


#将读入的内容添加到原字符串后面
my $buffer='START:';
my $byts = sysread(STDIN,$buffer, 10, length($buffer));
#my $byts = read(STDIN,$buffer, 10, length($buffer));
print $buffer,"
";

#将字符串添加到文件后面
open(FD, ">1.txt");
syswrite(FD,$buffer,10,2);
close(FD);
 
#sysread无缓冲/read有缓冲
#print有缓冲/syswrite无缓冲
#systead可设置追加偏移量
#syswrite可设置写入长度与开始写入的位置