UNIX filesystems have a feature called symbolic links, which are files that point to another file, called the target. They're similar to shortcuts in Windows.
There are two kinds of symbolic links: hard links and soft links.
Hard links create a file which points to the same space on the hard drive as the file which is being linked to, rather than to that file itself.
/home/me/file /home/you/file
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hard link hard link
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HARD DRIVE <....--``A file won't be deleted until every hard link to it is deleted.
To create a hard link, you use the ln command with the source file, and the target hard linked file:
Notice that any changes you make to arrayDat.txt will be reflected in arrayHard.txt.
Soft links create a file which points to the original file or directory.
Soft links break if the original file is deleted.
To create a soft link, you use the ln command with the -s flag.
Notice that any changes you make to arrayDat.txt will be reflected in arraySoft.txt. The ls command will show that arraySoft.txt points to the file arrayDat.txt.
Your Luria home folder has a couple of soft links automatically set up pointing to storage servers so that common programs don't take up too much space on the head node.
ln arrayDat.txt arrayHard.txt
ls/home/me/file <---Soft link--- /home/you/file
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HARD DRIVEln -s arrayDat.txt arraySoft.txt
ls -l