email-print-mime-structure: change --use-gpg-agent to a simple flag

Turns out that type=bool doesn't really do what we want it to do (see
https://bugs.python.org/issue37564), and there is no built-in easy
answer for argparse to accept a boolean value sensibly
(e.g. type='bool', which might be able to handle "yes" and "no" and
"1" and "0" and "on" and "off" as well as "true" and "false", etc)

So rather than implement all of that here, we'll just have
--use-gpg-agent as a simple flag.  This is an API change, but the
previous API has only been out for a few days, and the tool is
documented for interactive use.

Signed-off-by: Daniel Kahn Gillmor <dkg@fifthhorseman.net>

1 files changed, 6 insertions, 7 deletions

diff --git a/email-print-mime-structure.1.pod b/email-print-mime-structure.1.pod
index e4634e6..7201f48 100644
--- a/email-print-mime-structure.1.pod
+++ b/email-print-mime-structure.1.pod
@@ -32,19 +32,18 @@ key.
 OpenPGP secret keys listed in B<--pgpkey=> are used ephemerally, and
 do not interact with any local GnuPG keyring.
 
-=item B<--use-gpg-agent=>I<true>|I<false>
+=item B<--use-gpg-agent>
 
-If I<true>, and B<email-print-mime-structure> encounters a
-PGP/MIME-encrypted part, it will try to decrypt the part using the
-secret keys found in the local installation of GnuPG. (default:
-I<false>)
+If this flag is present, and B<email-print-mime-structure> encounters
+a PGP/MIME-encrypted part, it will try to decrypt the part using the
+secret keys found in the local installation of GnuPG.
 
-If both B<--pgpkey=>I<KEYFILE> and B<--use-gpg-agent=true> are
+If both B<--pgpkey=>I<KEYFILE> and B<--use-gpg-agent> are
 supplied, I<KEYFILE> arguments will be tried before falling back to
 GnuPG.
 
 If B<email-print-mime-structure> has been asked to decrypt parts with
-either B<--pgpkey=>I<KEYFILE> or with B<--use-gpg-agent=true>, and it
+either B<--pgpkey=>I<KEYFILE> or with B<--use-gpg-agent>, and it
 is unable to decrypt an encrypted part, it will emit a warning to
 stderr.