ulink,mkpath,rmtree

perl中的unlink: * unlink Deletes a list of files. On success, it returns the number of files it successfully deleted. On failure, it returns false and sets $! (errno): 1. my $unlinked = unlink 'a', 'b', 'c'; 2. unlink @goners; 3. unlink glob "*.bak"; On error, unlink will not tell you which files it could not remove. If you want to know which files you could not remove, try them one at a time: 1. foreach my $file ( @goners ) { 2. unlink $file or warn "Could not unlink $file: $!"; 3. } Note: unlink will not attempt to delete directories unless you are superuser and the -U flag is supplied to Perl. Even if these conditions are met, be warned that unlinking a directory can inflict damage on your filesystem. Finally, using unlink on directories is not supported on many operating systems. Use rmdir instead. If LIST is omitted, unlink uses $_ .2:mkpath and rmtree:File::Path有2个方法：mkpath和rmtree，分别为创建目录和删除目录。perl语言本身自带了 mkdir和rmdir，那为什么还要选用mkpath和rmtree呢？自带的mkdir只能一次创建一级目录，而mkpath则可以一次创建多级；rmdir必须要求目录为空，而rmtree则任意。总之，File::Path为我们提供了另一种创建和删除目录的机制，由用户自己选用。说明：a) mkpath(directory, 1, 0711);第一个参数为目录名，第二个参数为一个bool值，为真的时候打印每次创建的目录，默认为假，最后一个参数为目录的权限。b) rmtree(directory, 1, 1);第一个参数为目录名，第二个参数为一个bool值，为真的时候打印删除文件时的一些信息，默认为假，最后一个参数也是一个bool值，为真的时候对没有删除权限的文件直接跳过。http://perldoc.perl.org/File/Path.html