"--passphrase-fd n" not working

[Werner Koch]

On Mon, 01 Oct 2001 16:21:37 -0400, pd  said:

> I can't get it to work.  When I put in a filename it says it is
> looking for file descriptor 0.  Is the file descriptor here something
> different than the filename?  I tried inode number and that doesn't

Yes, it is different.  I suggest that you read some basic text on Unix
like Steven's APUE.  Or try it out:

The standard output is usually assigned to FD 1,  standard error to FD
2. You might have notices things like 

  foo 2>/dev/null

which sends all error output (standard error = FD 2) to the /dev/null
file/device.  Or the more common one:

  foo >myfile

which is the same as

  foo 1>myfile

So, why do we want to pass FD on the commandline?  Not all FD are
assigned to a file, oftne they are ahndles for pipes which are used
for interprocess communication like:

  foo | bar

where the shell build a pipe to direct the fd 1 of foo to the fd 0 of bar.

See the source of gpgme for an example on how to use this gpg
feature. strace may help you to get idea what's going on tehre.


Hth,

  Werner


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Werner Koch        Omnis enim res, quae dando non deficit, dum habetur
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