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I am trying to encrypt a file on-the-fly, redirecting the output to a named pipe [fifo]. I SSH into my server and run the command:

           $ mcrypt -k key < file > named_pipe

then from my laptop I try to scp it:

           $ scp me@server:~/dir/named_pipe 

and it says

           scp: /users/home/me/dir/named_pipe: not a regular file

Is there any way to do this? Thanks

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I would assume that scp copies file content. A named pipe is not a physical file, hence scp won't try to copy it (try copying /dev/random, for example). Just redirect to a file, or find a way to tunnel the data to your laptop. – new123456 Aug 2 '11 at 1:28
up vote 4 down vote accepted

Stream from it instead.

ssh me@server cat ~/dir/named_pipe > file.out
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So I finally got around to trying it out: this is what I get: Bus error: 10 (core dumped).. from mcrypt, and the "> file" file is emtpy. – Matt Aug 6 '11 at 2:26
Try streaming from the named pipe locally to see if mcrypt invokes a bus error even then. – Ignacio Vazquez-Abrams Aug 6 '11 at 2:57
Good call. I try it on a big file [900MB] and it seems to just sit there doing nothing [output being blank] So created a 5MB file from /dev/urandom, and tried encrypting to a regular file [no fifo]. And it invokes the bus error. :\ I try it on my local Ubuntu machine and it works fine. Maybe it's this server or freebsd? :\ Do you of any encryption program to output to stdout? – Matt Aug 6 '11 at 13:16
Unfortunately command-line encryption is not my forte; I usually leave that to GnuPG or OpenSSL. – Ignacio Vazquez-Abrams Aug 6 '11 at 17:38
Turns out, I don't need this anymore. However, your answer would have worked if mcrypt would work. :) – Matt Aug 6 '11 at 23:20

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