Perl -- print a block text; file test; chmod

1)
print <
test line one
test line two
...
EOF

2)-e 测试文件或文件夹是否存在
print -e "directory1/file.txt"; ##true while return 1;

if(-e "directory1/file.txt"){
print "file exists. \n";
}else{
print "file doesn't exists. \n";
}

-z 测试文件是不是零size true返回1
-s 测试none 零size 返回文件的尺寸数
-d 测试是不是文件夹 true返回1

3)chmod set file permissions
chmod 0644, 'directory1/file.txt';
chmod 0755, 'directory1';

@files = ("directory1/file1.txt", "directory1/file2.txt");
chmod 0644, @files; ##成批文件更改

#files 0644, 0666
#directorys 0755, 0777
#perl scripts 0755