Basic Unix Commands - File System the File

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Basic Unix Commands - File System The File UNIX treats everything as a le... Directories and devices like the hard disk, DVD-ROM, and printer are les to UNIX. Three types of les 1. Ordinary le Also known as a regular le, contains only data as a stream of characters. 2. Directory le A folder containing the names of other les and subdirectories. 3. Device le Represents a device or peripheral. The File System Hierarchy UNIX les are organized in a hierarchical (an inverted tree) structure, starting with root (/) Image Source: S. Das. Your UNIX/Linux: The Ultimate Guide. Third. McGraw-Hill, Inc., Relative Pathnames Relative path shortcuts . (a single dot) represents the current directory .. (two dots) represents the parent directory Example > pwd /home > ls . john george > cd john $ pwd /home/john > cd .. > pwd /home Making and removing directories Making directories >mkdir myDir (UNIX is case sensitive by-the-way) creates a directory myDir in the current directory >mkdir myDir1 myDir2 Creates multiple directories in one command >mkdir myDir1/myDir2 creates myDir2 inside of myDir1 (must exist) Removing directories rmdir myDir Only works for empty directories. (No other les/directories inside) rm -R myDir Use will caution! You CANNOT recover from rm Copy and Move cp -- copy >cp file1 file2 Copies file1 to file2 >cp -R myDir1 myDir2 -R option copies recursively, meaning all subdirectories will be copied as well mv - move >mv file1 file2 When used this way it’s basically a rename utility >mv file1 file2 myDir Moves file1 and file2 into the directory myDir Deleting les >rm file1 file2 >rm file* * is a wildcard, meaning anything, the command will remove all patterns that match le with anything following. Can be dangerous. With the right permissions rm -Rf /* would remove most of the les on your hard drive without warning. Protect yourself rm -i.

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