unix-linux.json

{
  "sections": [
    {
      "title": "File System",
      "commands": [
        {
          "command": "ls",
          "description": "list items in current directory"
        },
        {
          "command": "ls -l",
          "description": "list items in current directory and show in long format to see perimissions, size, and modification date"
        },
        {
          "command": "ls -a",
          "description": "list all items in current directory, including hidden files"
        },
        {
          "command": "ls -F",
          "description": "list all items in current directory and show directories with a slash and executables with a star"
        },
        {
          "command": "ls dir",
          "description": "list all items in directory dir"
        },
        {
          "command": "cd dir",
          "description": "change directory to dir"
        },
        {
          "command": "cd ..",
          "description": "go up one directory"
        },
        {
          "command": "cd /",
          "description": "go to the root directory"
        },
        {
          "command": "cd ~",
          "description": "go to to your home directory"
        },
        {
          "command": "cd -",
          "description": "go to the last directory you were just in"
        },
        {
          "command": "pwd",
          "description": "show present working directory"
        },
        {
          "command": "mkdir dir",
          "description": "make directory dir"
        },
        {
          "command": "rm file",
          "description": "remove file"
        },
        {
          "command": "rm -r dir",
          "description": "remove directory dir recursively"
        },
        {
          "command": "cp file1 file2",
          "description": "copy file1 to file2"
        },
        {
          "command": "cp -r dir1 dir2",
          "description": "copy directory dir1 to dir2 recursively"
        },
        {
          "command": "mv file1 file2",
          "description": "move (rename) file1 to file2"
        },
        {
          "command": "ln -s file link",
          "description": "create symbolic link to file"
        },
        {
          "command": "touch file",
          "description": "create or update file"
        },
        {
          "command": "cat file",
          "description": "output the contents of file"
        },
        {
          "command": "less file",
          "description": "view file with page navigation"
        },
        {
          "command": "head file",
          "description": "output the first 10 lines of file"
        },
        {
          "command": "tail file",
          "description": "output the last 10 lines of file"
        },
        {
          "command": "tail -f file",
          "description": "output the contents of file as it grows, starting with the last 10 lines"
        },
        {
          "command": "vim file",
          "description": "edit file"
        },
        {
          "command": "alias name 'command'",
          "description": "create an alias for a command"
        }
      ]
    },
    {
      "title": "System",
      "commands": [
        {
          "command": "shutdown",
          "description": "shut down machine"
        },
        {
          "command": "reboot",
          "description": "restart machine"
        },
        {
          "command": "date",
          "description": "show the current date and time"
        },
        {
          "command": "whoami",
          "description": "who you are logged in as"
        },
        {
          "command": "finger user",
          "description": "display information about user"
        },
        {
          "command": "man command",
          "description": "show the manual for command"
        },
        {
          "command": "df",
          "description": "show disk usage"
        },
        {
          "command": "du",
          "description": "show directory space usage"
        },
        {
          "command": "free",
          "description": "show memory and swap usage"
        },
        {
          "command": "whereis app",
          "description": "show possible locations of app"
        },
        {
          "command": "which app",
          "description": "show which app will be run by default"
        }
      ]
    },
    {
      "title": "Process Management",
      "commands": [
        {
          "command": "ps",
          "description": "display your currently active processes"
        },
        {
          "command": "top",
          "description": "display all running processes"
        },
        {
          "command": "kill pid",
          "description": "kill process id pid"
        },
        {
          "command": "kill -9 pid",
          "description": "force kill process id pid"
        }
      ]
    },
    {
      "title": "Permissions",
      "commands": [
        {
          "command": "ls -l",
          "description": "list items in current directory and show permissions"
        },
        {
          "command": "chmod ugo file",
          "description": "change permissions of file to ugo - u is the user's permissions, g is the group's permissions, and o is everyone else's permissions.  The values of u, g, and o can be any number between 0 and 7."
        },
        {
          "command": 7,
          "description": "full permissions"
        },
        {
          "command": 6,
          "description": "read and write only"
        },
        {
          "command": 5,
          "description": "read and execute only"
        },
        {
          "command": 4,
          "description": "read only"
        },
        {
          "command": 3,
          "description": "write and execute only"
        },
        {
          "command": 2,
          "description": "write only"
        },
        {
          "command": 1,
          "description": "execute only"
        },
        {
          "command": 0,
          "description": "no permissions"
        },
        {
          "command": "chmod 600 file",
          "description": "you can read and write - good for files"
        },
        {
          "command": "chmod 700 file",
          "description": "you can read, write, and execute - good for scripts"
        },
        {
          "command": "chmod 644 file",
          "description": "you can read and write, and everyone else can only read - good for web pages"
        },
        {
          "command": "chmod 755 file",
          "description": "you can read, write, and execute, and everyone else can read and execute - good for programs that you want to share"
        }
      ]
    },
    {
      "title": "Networking",
      "commands": [
        {
          "command": "wget file",
          "description": "download a file"
        },
        {
          "command": "curl file",
          "description": "download a file"
        },
        {
          "command": "scp user@host:file dir",
          "description": "secure copy a file from remote server to the dir directory on your machine"
        },
        {
          "command": "scp file user@host:dir",
          "description": "secure copy a file from your machine to the dir directory on a remote server"
        },
        {
          "command": "scp -r user@host:dir dir",
          "description": "secure copy the directory dir from remote server to the directory dir on your machine"
        },
        {
          "command": "ssh user@host",
          "description": "connect to host as user"
        },
        {
          "command": "ssh -p port user@host",
          "description": "connect to host on port as user"
        },
        {
          "command": "ssh-copy-id user@host",
          "description": "add your key to host for user to enable a keyed or passwordless login"
        },
        {
          "command": "ping host",
          "description": "ping host and output results"
        },
        {
          "command": "whois domain",
          "description": "get information for domain"
        },
        {
          "command": "dig domain",
          "description": "get DNS information for domain"
        },
        {
          "command": "dig -x host",
          "description": "reverse lookup host"
        },
        {
          "command": "lsof -i tcp:1337",
          "description": "list all processes running on port 1337"
        }
      ]
    },
    {
      "title": "Searching",
      "commands": [
        {
          "command": "grep pattern files",
          "description": "search for pattern in files"
        },
        {
          "command": "grep -r pattern dir",
          "description": "search recursively for pattern in dir"
        },
        {
          "command": "grep -rn pattern dir",
          "description": "search recursively for pattern in dir and show the line number found"
        },
        {
          "command": "grep -r pattern dir --include='*.ext",
          "description": "search recursively for pattern in dir and only search in files with .ext extension"
        },
        {
          "command": "command | grep pattern",
          "description": "search for pattern in the output of command"
        },
        {
          "command": "find file",
          "description": "find all instances of file in real system"
        },
        {
          "command": "locate file",
          "description": "find all instances of file using indexed database built from the updatedb command.  Much faster than find"
        },
        {
          "command": "sed -i 's/day/night/g' file",
          "description": "find all occurrences of day in a file and replace them with night - s means substitude and g means global - sed also supports regular expressions"
        }
      ]
    },
    {
      "title": "Compression",
      "commands": [
        {
          "command": "tar cf file.tar files",
          "description": "create a tar named file.tar containing files"
        },
        {
          "command": "tar xf file.tar",
          "description": "extract the files from file.tar"
        },
        {
          "command": "tar czf file.tar.gz files",
          "description": "create a tar with Gzip compression"
        },
        {
          "command": "tar xzf file.tar.gz",
          "description": "extract a tar using Gzip"
        },
        {
          "command": "gzip file",
          "description": "compresses file and renames it to file.gz"
        },
        {
          "command": "gzip -d file.gz",
          "description": "decompresses file.gz back to file"
        }
      ]
    },
    {
      "title": "Shortcuts ",
      "commands": [
        {
          "command": "ctrl+a",
          "description": "move cursor to beginning of line"
        },
        {
          "command": "ctrl+f",
          "description": "move cursor to end of line"
        },
        {
          "command": "alt+f",
          "description": "move cursor forward 1 word"
        },
        {
          "command": "alt+b",
          "description": "move cursor backward 1 word"
        }
      ]
    }
  ]
}