against file which has hard link to another file

You actually only have one file on disk (uniquely identified by the device and inode values, see stat and lstat) with, in effect, two references to it in the directory table. You can have multiple hard links all pointing to the same file if you like. Any change to one will appear in all of them. However, deleting one of them will leave the others in place.

$ echo "hello world" > xxyyzz
$ ln xxyyzz aabbcc
$ ln xxyyzz ddeeff
$ ls -li aabbcc ddeeff xxyyzz 
     45063 -rw-r--r--   3 root     root          12 Aug  7 23:36 aabbc
+c
     45063 -rw-r--r--   3 root     root          12 Aug  7 23:36 ddeef
+f
     45063 -rw-r--r--   3 root     root          12 Aug  7 23:36 xxyyz
+z
$ cat aabbcc 
hello world
$ echo bye >> ddeeff 
$ cat xxyyzz 
hello world
bye
$ rm aabbcc
$ ls -li aabbcc ddeeff xxyyzz
aabbcc: No such file or directory
     45063 -rw-r--r--   2 root     root          16 Aug  7 23:38 ddeef
+f
     45063 -rw-r--r--   2 root     root          16 Aug  7 23:38 xxyyz
+z
$

[download]

I hope this helps you.

Cheers,

JohnGG

In reply to Re: file input output problem by johngg
in thread file input output problem by convenientstore

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