Hi,
1. bash version: GNU bash, version 4.2.10(1)-release (x86_64-pc-linux-gnu)
2. test script:
[bash] #!/bin/bash
[bash] remote_ssh_account="depesz@localhost"
[bash] directory_to_tar=pgdata
[bash] exec nice tar cf - "$directory_to_tar" | \
[bash] tee >(
[bash] md5sum - | \
[bash] ssh "$remote_ssh_account" 'cat - > /tmp/h3po4-MD5-2012-03-13.tar'
[bash] ) | \
[bash] ssh "$remote_ssh_account" 'cat - > /tmp/h3po4-data-2012-03-13.tar'
exec+nice are irrelevant - without them happens the same thing.
to test it you need directory (pgdba in this case) with non-trivial size
(i test on 1.5GB), and remote (over ssh) account with passwordless
authentication (depesz@localhost in here).
When I run it, I get
tee: standard output: Resource temporarily unavailable
i.e. the "data" ssh seems to fail.
But I did strace, and it looks that this ssh is not getting any data
from anywhere, despite the fact that tee *does* write the data to 1st
fd.
talked about the problem on #bash, and they suggested to change it to:
[bash] #!/bin/bash
[bash] remote_ssh_account="depesz@localhost"
[bash] directory_to_tar=pgdata
[bash] nice tar cf - "$directory_to_tar" | \
[bash] tee >(
[bash] md5sum | \
[bash] ssh "$remote_ssh_account" 'cat > /tmp/h3po4-MD5-2012-03-13.sum'
[bash] ) > >(
[bash] ssh "$remote_ssh_account" 'cat > /tmp/h3po4-data-2012-03-13.tar'
[bash] )
which works.
I also tested version:
[bash] #!/bin/bash
[bash] remote_ssh_account="depesz@localhost"
[bash] directory_to_tar=pgdata
[bash] nice tar c "$directory_to_tar" | \
[bash] tee >(
[bash] md5sum - | \
[bash] ssh "$remote_ssh_account" 'cat - > /tmp/h3po4-MD5-2012-03-13.tar'
[bash] ) >(
[bash] ssh "$remote_ssh_account" 'cat - > /tmp/h3po4-data-2012-03-13.tar'
[bash] ) > /dev/null
It looks that the final pipe breaks. Any idea on what could be wrong?
Best regards,
depesz
--
The best thing about modern society is how easy it is to avoid contact with it.
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