我们知道“Linux 中的一切”都是文件，而且目录只是包含其他文件的文件。
所以，我不知道这个“疯狂的想法”是否可行，但它应该以某种方式符合上述原则。
简单来说，我怎样才能将现有的空文件更改为目录。这可能吗？
经过一番头脑风暴，我想到对文件元数据进行一些修改并将其作为目录元数据就可以了！！
任何提供的信息都将受到赞赏。
更新：当然，我不想删除文件并创建目录！我只是想知道，如果您可以使用一些文件元数据，上述哲学的适用程度如何。
答案1
实现转换
创建测试文件系统
为了在运行此实验后保护我们的主要文件系统免受任何可能的损坏，我们将在普通文件中创建一个小型文件系统以用于测试目的。
创建一个名为 的零填充文件，
test大小为 10 兆字节：dd if=/dev/zero of=~/test bs=10M count=1在文件内部创建一个 Ext4 文件系统，就像它是一个分区一样：
mkfs.ext4 ~/test
创建一些文件和目录
现在我们在test文件内部有一个功能齐全的文件系统，所以我们将在其中创建一些文件和目录。
将新创建的文件系统挂载到里面
/mnt：sudo mount ~/test /mnt创建文件和目录：
sudo mkdir /mnt/folder echo "contents" | sudo tee /mnt/file检查文件系统的内容：
ls -l /mnt输出应该是这样的：
total 2 -rw-r--r-- 1 root root 0 may 21 18:53 file drw-r--r-- 2 root root 1024 may 21 18:55 folder卸载测试文件系统：
sudo umount /mnt
交换文件和文件夹
debugfs针对具有写权限的文件运行test（-w标志）：debugfs -w ~/test转换
file成文件夹：在
debugfs提示符下，输入以下内容：modify_inode file将出现一个提示，询问您一种模式；输入以下内容：
040644继续按return保留剩余数据，直到再次出现提示。
转换
folder成文件：在
debugfs提示符下，输入以下内容：modify_inode folder将出现一个提示，询问您一种模式；输入以下内容：
0100644继续按return保留剩余数据，直到再次出现提示。
要退出
debugfs提示，只需点击q进而return
检查操作是否成功
再次挂载测试文件系统：
sudo mount ~/test /mnt检查文件系统内容：
ls -l /mnt现在，它应该将文件显示为目录，并且反之亦然：
total 2 drw-r--r-- 1 root root 0 may 21 18:53 file -rw-r--r-- 2 root root 1024 may 21 18:55 folder
计算 inode 模式的脚本
#!/bin/bash
#### See https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout#Inode_Table
## Terminal measures:
x="$(( $(tput cols) / 2 ))" # Width of the terminal
y="$(( $(tput lines) / 2 ))" # Height of the terminal
## File descriptors:
declare -A types # Declare an associative array with file descriptors
types[f]='0x8000' # File
types[l]='0xA000' # Link
types[s]='0xC000' # Socket
types[d]='0x4000' # Directory
types[p]='0x1000' # Named pipe
types[b]='0x6000' # Block device
types[c]='0x2000' # Character device
## Permissions:
declare -A permission # Declare an associative array with permissions
permission[user_S]='0x800' # UID
permission[user_s]='0x840' # UID and user can execute
permission[user_r]='0x100' # User can read
permission[user_w]='0x80' # User can write
permission[user_x]='0x40' # User can execute
permission[group_S]='0x400' # GID
permission[group_s]='0x408' # GID and group can execute
permission[group_r]='0x20' # Group can read
permission[group_w]='0x10' # Group can write
permission[group_x]='0x8' # Group can execute
permission[other_T]='0x200' # Sticky bit
permission[other_t]='0x201' # Sticky bit and other can execute
permission[other_r]='0x4' # Other can read
permission[other_w]='0x2' # Other can write
permission[other_x]='0x1' # Other can execute
## Cleanup function:
function cleanup() {
tput cvvis # Make the cursor visible
tput rmcup # Restore saved terminal contents
stty sane # Fix problems caused by read -s
exit 0 # Exit gracefully
}
## Function to print at a specified position:
function pprint() {
tput cup $1 $2
printf "${@:3}"
}
## Function to clear the notification area:
function reset() {
pprint $((y+2)) $((x-40)) ' %.0s' {1..25} # Print 25 spaces
}
## Function to notify something to the user:
function notify() {
reset # Clear the notification area
pprint $((y+2)) $((x-40)) "$@" # Print the notification text
}
## If the terminal is smaller than 100x8, exit gracefully (self-explainatory):
if [ $x -lt 50 ] || [ $y -lt 5 ]; then
echo 'Error, I need a minimum of 100x10 lines to run'
exit 0
fi
## Initialize the terminal:
trap cleanup EXIT SIGHUP SIGINT SIGTERM # Call cleanup function after receiving ^C
stty -echo cbreak # Put terminal in silent mode
tput smcup # Save terminal contents
tput civis # Make the cursor inisible
## Draw the big box:
printf '\033[1;37m' # Color
pprint $((y-3)) $((x-48)) '\u2500%.0s' {1..97} # Upper line
pprint $((y+4)) $((x-48)) '\u2500%.0s' {1..97} # Lower line
for ((i=4;i>-4;i--)); do # Sides:
pprint $((y+i)) $((x-49)) '\u2502' # Left line
pprint $((y+i)) $((x+49)) '\u2502' # Right line
done # End sides
pprint $((y-3)) $((x-49)) '\u256D' # Upper-left corner
pprint $((y+4)) $((x-49)) '\u2570' # Lower-left corner
pprint $((y-3)) $((x+49)) '\u256E' # Upper-right corner
pprint $((y+4)) $((x+49)) '\u256F' # Lower-right corner
## Draw the small box:
printf '\033[1;35m' # Color
pprint $((y+1)) $((x-10)) '\u2501%.0s' {1..10} # Upper line
pprint $((y+3)) $((x-10)) '\u2501%.0s' {1..10} # Lower line
pprint $((y+2)) $((x-11)) '\u2503' # Left line
pprint $((y+2)) $((x+00)) '\u2503' # Right line
pprint $((y+1)) $((x-11)) '\u250F' # Upper-left corner
pprint $((y+3)) $((x-11)) '\u2517' # Lower-left corner
pprint $((y+1)) $((x+00)) '\u2513' # Upper-right corner
pprint $((y+3)) $((x+00)) '\u251B' # Lower-right corner
## Print type help:
pprint $((y-2)) $((x-44)) '\033[0;37mInode type: \033[1;37mf\033[0;37mile, \033[1;37md\033[0;37mirectory, \033[1;37ml\033[0;37mink, named \033[1;37mp\033[0;37mipe, \033[1;37ms\033[0;37mocket, \033[1;37mc\033[0;37mharacter device or \033[1;37mb\033[0;37mlock device.'
## Print permission help:
pprint $((y-1)) $((x-40)) '\033[0;36mPermission (\033[1;32mu\033[0;32mser\033[0;36m, \033[1;33mg\033[0;33mroup\033[0;36m or \033[1;31mo\033[0;31mther\033[0;36m): \033[1;36mr\033[0;36mead, \033[1;36mw\033[0;36mrite, e\033[1;36mx\033[0;36mecute, \033[1;36mhyphen\033[0;36m or \033[1;36mspace\033[0;36m to skip.'
pprint $((y+0)) $((x+8)) 's\033[1;36mt\033[0;36micky bit and executable, '
pprint $((y+1)) $((x+8)) 's\033[1;36mT\033[0;36micky bit not executable, '
pprint $((y+2)) $((x+8)) '\033[1;36ms\033[0;36metuid/setgid and executable, '
pprint $((y+3)) $((x+8)) '\033[1;36mS\033[0;36metuid/setgid not executable. '
## Endless loop:
while :; do
## Clear the input area:
pprint $((y+2)) $((x-10)) '% *s\n' 10 # Print 16 spaces
## Print mask in the input area:
printf '\033[1;37m' # Color for the type
pprint $((y+2)) $((x-10)) '\u2588' # Block for the type
printf '\033[1;36m' # Color for the permision
pprint $((y+2)) $((x- 9)) '\u2588%.0s' {1..9} # Blocks for the permission
## Loop through all variables to make a proper input:
for var in type {user,group,other}_{r,w,x}; do
## Assign colors and regex to fields:
case "$var" in
(type) color='\033[1;37m'; regex='^[fdlpscb]$' ;;
(other_x) regex='^[-xtT]$' ;;&
(user_x|group_x) regex='^[-xsS]$' ;;&
(user_[rw]|group_[rw]|other_[rw]) regex="^[-${var: -1}]$";;&
(user*) color='\033[1;32m' ;;
(group*) color='\033[1;33m' ;;
(other*) color='\033[1;31m' ;;
esac
## Change the pointer position:
pprint $((y+3)) $(((x-10)+pointer)) "${color}\u2501" # Print the pointer on its new position
if (( pointer > 0 )); then # If the pointer is not in the first position:
pprint $((y+3)) $(((x-10)+(pointer-1))) '\033[1;35m\u2501' # Clear the old pointer
fi
## Infinite loop until there is a valid input for the current character:
while :; do
printf "$color" # Set the character color
IFS= read -rn 1 $var # Read a character (even if it's a space)
declare $var="${!var// /-}" # Convert spaces to hyphens.
if [[ "$var" == "type" ]]; then # If the current variable is type:
declare $var="${!var//-/f}" # Convert "-" to "f"
fi
if [[ "${!var}" =~ $regex ]]; then # If there is a valid input:
reset # Clear error notification if any
break # Exit from this loop
else # Else:
notify "\033[1;31mWrong input!" # Print the error message
fi
done
## Print the entered value:
pprint $((y+2)) $(((x-10)+pointer)) "${!var}"
## Sum the current permission:
((mode+=permission[${var%_*}_${!var}]))
## Increment the pointer:
((pointer++))
done
## Post-read:
unset pointer # Reset the pointer
pprint $((y+3)) $((x-1)) "\033[1;35m\u2501" # Clear the pointer
read -n 1 # Wait for Return or another character
## Sum file descriptor type:
((mode+=${types[$type]}))
## Final commands:
mode=$(printf "%o" $mode) # Convert mode to octal (before this was decimal)
notify "\033[1;32mOctal mode:\033[1;34m $mode" # Print the octal mode
unset mode # Reset the mode
done
障碍
- 文件夹无法打开。你无法打开它除非您将最初包含它的“原始文件夹数据”放在上面。
进一步阅读
https://ext4.wiki.kernel.org/index.php/Ext4_Disk_Layout#Inode_Table
谢谢@tallus。他给了我一个很好的提示：
debugfs 有一个modify_inode命令，允许您直接编辑inode，从而允许您将文件标志设置为目录。