topic Re: where is my problem in Operating System - HP-UX

where is my problem

Seshadri Dehalisan — Mon, 06 Dec 1999 13:14:05 GMT

Hi all,
My machine is HP-UX B.10.20 C 9000/869 running HP-UX 10.20 .
I am having problem with the following commands though iam not able to isolate
where the problem is

compresssesha.Z &
dd if=/oracle/dbfile/user_2_file of=/user/backup/seshapipe bs=1048576
if test $? -ne 0 ; then echo "ERROR in backing up the database to
destination directory "

where /user/backup/seshapipe is an unix pipe created with command mknod p
/user/backup/seshapipe

Basically what iam trying to do is to compress the file in fly .

All my files are 2G.

Many times when i try to compress these files iam getting the compressed file
which is
150 bytes or so and when i try to uncompress iam not getting my file back.

Am i missing anything or iam hitting some bug

Any help will be greatly appreciated

Thanks
Seshadri

Re: where is my problem

Dan Hull — Mon, 06 Dec 1999 16:55:57 GMT

What is "compresssesha.Z" ? Is there supposed to be a space there? Is this part
of the script, or is it the name of it? Normally you don't compress a file that
already has a .Z extension.

Where/what does the "seshapipe" point to?

Re: where is my problem

Seshadri Dehalisan — Mon, 06 Dec 1999 19:51:03 GMT

Hi ,
Iam sorry i obviously missed when i did a cut and paste.
The commands will look as follow
compresscompresssesha.Z &
dd if=/oracle/dbfile/user_2_file of=/user/backup/seshapipe bs=1048576
if test $? -ne 0 ; then echo "ERROR in backing up the datafile to destination
directory "

Here seshapipe is an unix pipe created using the command
mknod seshapipe p
What i try to acheive by using this command is to compress the file online
while taking backup.(these are oracle datafiles).The file iam trying to backup
is 2Gb and attimes the compressed file is 140 bytes or so which is really
weird.I donot get the same file back when i try to uncompress this 140 bytes
file.
So iam wondering if there are any bugs with unix pipes
when i get this 140 bytes compress file the $? is 0 which is successful
completion of dd and iam not able to get the return value for compress as it
runs in background

Thanks for correcting me
Any help will be greatly appreciated
Seshadri

Re: where is my problem

Asad Malik_1 — Tue, 07 Dec 1999 11:45:07 GMT

Hi
I have the same question, what is meant by first line and are you trying to
compress an already copressed file or does the script start with dd command.
Thanks

Re: where is my problem

Seshadri Dehalisan — Tue, 07 Dec 1999 13:47:05 GMT

Hi ,
I am sorry for reasons unknown few characters are not getting printed .i typed
output and input redirection symbols and it's not getting printed in this
forum.so i have attached it as a text.
anyway iam not trying to compress a file that has been already compressed .my
first line is simply this
compress"<"seshapipe">"sesha.Z &
please read with the double quotes removed.
Thanks

any help will be appreciated

Thanks
Seshadri