Chmod 计算器 - Linux 文件权限网格
不必记住八进制代码，而是检查所有者、组和公共的读取、写入和执行 - Dokall 立即显示八进制值、符号表示法和准备粘贴的 chmod 命令。
常见预设包括用于 Web 目录的 755、用于文件的 644、用于 SSH 密钥的 600 以及用于只读 PEM 密钥的 400。在复制之前编辑文件名字段以自定义终端命令。
Frequently Asked Questions
What is chmod?
chmod (change mode) is a Unix/Linux command that sets file permissions. It controls who can read, write, and execute a file - the owner, the group, and everyone else.
What do the numbers in chmod 755 mean?
Each digit represents permissions for owner, group, and others. 7 = read(4) + write(2) + execute(1). 5 = read(4) + execute(1). So 755 means owner has full access, group and others can read and execute but not write.
What is the difference between files and directories?
Execute permission on a file means it can be run as a program. Execute on a directory means you can cd into it and list its contents. Directory permissions 755 (rwxr-xr-x) are standard; file permissions 644 (rw-r--r--) are common for regular files.
What does chmod 777 do?
777 grants read, write, and execute to everyone - owner, group, and others. This is a security risk on servers because any user can modify the file. Use 755 for directories and 644 for files unless you have a specific reason for broader access.
Symbolic vs numeric notation?
Numeric (755) is compact and common in tutorials. Symbolic (u=rwx,g=rx,o=rx) is more readable and used in chmod commands with letters: chmod u+x file adds execute for the owner. Dokall converts between both formats.