tar bzip2, pipe, error ?

[Libor Chocholaty]

Dusan Zatkovsky wrote:

>DD.
>
>Upravujem svoj backup script, aby pouzival gpg sifrovanie na zalohy a narazil 
>som na nasledovny problem. Mozete mi prosim niekto vysvetlit, co robim zle? 
>Nech sa akokolvek snazim, na nic neprichadzam.
>
>
>Vytvorim jeden a ten isty archiv 4mi sposobmi:
>
>	A	[msk na localhost d]$ ls
>	A	data/
>	A	[msk na localhost d]$ tar cjvf normal.tar.bz2 data
>	A	data/
>	A	data/file
>	A	[msk na localhost d]$ ls
>	A	data/  normal.tar.bz2
>
>
>	B	[msk na localhost d]$ tar cjvf - data > pipe.tar.bz2
>	B	data/
>	B	data/file
>	B	[msk na localhost d]$ ls
>	B	data/  normal.tar.bz2  pipe.tar.bz2
>
>
>	C	[msk na localhost d]$ mkfifo fifo
>	C	[msk na localhost d]$ tar cjvf fifo data &
>	C	data/
>	C	data/file
>	C	[1] 22581
>	C	[msk na localhost d]$ cat fifo > fifo.tar.bz2
>	C	ls
>	C	[1]+  Done                    tar cjvf fifo data
>	C	[msk na localhost d]$ ls
>	C	data/  fifo|  fifo.tar.bz2  normal.tar.bz2  pipe.tar.bz2
>
>
>	D	[msk na localhost d]$ tar cj data > pipe-nonverbose.tar.bz2
>	D	[msk na localhost d]$ ls
>	D	data/  fifo|  fifo.tar.bz2  normal.tar.bz2  pipe-nonverbose.tar.bz2
>	D	pipe.tar.bz2
>
>Co mi vzniklo:
>
>	[msk na localhost d]$ ls -la
>	total 27144
>	drwxr-xr-x   3 msk msk    4096 zář 14 13:52 ./
>	drwx------  33 msk msk    4096 zář 14 11:52 ../
>	drwxr-xr-x   2 msk msk    4096 zář 14 13:47 data/
>	prw-r--r--   1 msk msk       0 zář 14 13:50 fifo|
>	-rw-r--r--   1 msk msk 6932480 zář 14 13:50 fifo.tar.bz2
>	-rw-r--r--   1 msk msk 6927642 zář 14 13:48 normal.tar.bz2
>	-rw-r--r--   1 msk msk 6932480 zář 14 13:53 pipe-nonverbose.tar.bz2
>	-rw-r--r--   1 msk msk 6932480 zář 14 13:49 pipe.tar.bz2
>
>
>
>Spravim md5sum:
>
>	[msk na localhost d]$ md5sum *.tar.bz2
>	2618b8f47625c8cbcc14ef0f89107ca9  fifo.tar.bz2
>	70e16b7379030665926ff8675c43d285  normal.tar.bz2
>	2618b8f47625c8cbcc14ef0f89107ca9  pipe-nonverbose.tar.bz2
>	2618b8f47625c8cbcc14ef0f89107ca9  pipe.tar.bz2
>
>
>
>Skusim otestovat vzniknute archivy:
>
>	A	[msk na localhost d]$ tar tjvf normal.tar.bz2
>	A	drwxr-xr-x msk/msk           0 2005-09-14 13:47:18 data/
>	A	-rwxr-xr-x msk/msk     6976776 2004-02-23 12:51:00 data/file
>
>
>	B	[msk na localhost d]$ tar tjvf pipe.tar.bz2
>	B	drwxr-xr-x msk/msk           0 2005-09-14 13:47:18 data/
>	B	-rwxr-xr-x msk/msk     6976776 2004-02-23 12:51:00 data/file
>	B	bzip2: (stdin): trailing garbage after EOF ignored
>
>	C	[msk na localhost d]$ tar tjvf fifo.tar.bz2
>	C	drwxr-xr-x msk/msk           0 2005-09-14 13:47:18 data/
>	C	-rwxr-xr-x msk/msk     6976776 2004-02-23 12:51:00 data/file
>	C	bzip2: (stdin): trailing garbage after EOF ignored
>
>
>	D	[msk na localhost d]$ tar tjvf pipe-nonverbose.tar.bz2
>	D	drwxr-xr-x msk/msk           0 2005-09-14 13:47:18 data/
>	D	-rwxr-xr-x msk/msk     6976776 2004-02-23 12:51:00 data/file
>	D	bzip2: (stdin): trailing garbage after EOF ignored
>
>
>Co moze sposobovat to, ze vsetky archivy, ktore vznikli za pouzitia pipe, su 
>vadne (resp. obsahuju 38 bajtov nul navyse a bzip2 to znervoznuje)?
>
>
>  
>
Zkus na kazdy z nich postvat info a zkontroluj, zda nemaji pouzitou 
jinou kompresi.
Taky me napada, ze soubory budou mit jine timestampy, coz se taky 
projevi v kontrolnim souctu.

Libor