Here is the actual error. how to overcome in AIX 6.1
Some of the users have bash shell and some have ksh.

#gpg-connect-agent 'getinfo version' /bye
gpg-connect-agent: can't connect to the agent: IPC connect call failed

What is the output of

  gpgconf --list-dirs

?

Werner,

Thanks for your response. Here is the requested output.

sysconfdir:/opt/freeware/etc/gnupg
bindir:/opt/freeware/bin
libexecdir:/opt/freeware/libexec
libdir:/opt/freeware/lib/gnupg
datadir:/opt/freeware/share/gnupg
localedir:/opt/freeware/share/locale
dirmngr-socket:/var/run/dirmngr/socket
agent-socket://.gnupg/S.gpg-agent
homedir://.gnupg

Good news is gpg2 is functioning now.
I have resolved the issues by following some of your recommendations.
We are able to generate keys however there are still some issues that should
be fixed on AIX 6.1 system. Also we wonder if there are known bugs in
gpg2.0.29 on AIX 6.1

Here is the list of rpm packages installed.

zlib-1.2.8-1
pth-2.0.7-3
gcc-cpp-4.8.3-1
libgomp-4.8.3-1
gcc-c++-4.8.3-1
curl-7.47.0-1
hexdump-20130926-1
bash-4.2-3
bzip2-1.0.6-1
libffi-3.2.1-1
libgcrypt-1.5.4-1
libiconv-1.14-2
libidn-1.29-1
info-5.2-1
libassuan-2.4.2-1
openldap-2.4.23-0.3
libgcc-4.8.3-1
libksba-1.3.0-1
libssh2-1.4.3-2
gpgme-1.6.0-1
npth-1.2-1
readline-6.3-5
libgpg-error-1.21-1
expat-2.1.0-1
glib2-2.38.2-1
libstdc++-4.8.3-1
pkg-config-0.28-1
libssh2-docs-1.4.3-2
gmp-5.1.3-1
mpfr-3.1.2-1
libmpc-1.0.2-1
libstdc++-devel-4.8.3-1
gcc-4.8.3-1
gettext-0.17-1
gnupg-1.4.20-1
gnupg2-2.0.26-1
openssl-1.0.1r-2

Here is the history of what I have done to fix the issue.

Downloaded source packages from https://www.gnupg.org/
Compiled libgpg-error,pinentry-0.9.7,libgcrypt-1.6.5,libassuan-2.4.2,
libksba-1.3.3 and compiled the below two packages in a different way.

pth-2.0.7

./configure --with-fdsetsize=8192
make
make install

gnupg-2.0.29

ulimit -H -n 8192; CC="gcc -DFD_SETSIZE=8192" ./configure
ulimit -H -n 8192; CC="gcc -DFD_SETSIZE=8192" make
ulimit -H -n 8192; CC="gcc -DFD_SETSIZE=8192" make install

And even while generating the keys I have to set the ulimits (nofiles to

8192. on AIX system which I think it won't work on real time systems.

Currently gpg1, gpg2 (2.0.26) and gpg2 (2.0.29) are co-existing on the
system.

Would you please assist me on how to overcome this nofiles ( ulimit ) issue.
I wish to use plain command i.e., gpg2 --gen-keys instead of ulimit -Hn
8192;gpg2 --gen-keys everytime.

For sure I cannot change the nofiles (ulimit value) at OS level as it may
impact the running application.
Kindly let me know if there are any patches that should be installed.

Also please Share the pricing / support model information if your company is
offering enterprise level support.

Thanks
Sandeep

It seems $HOME is not set in your environment and thus you see the double-slash
for agent-socket and homedir. gpg uses ~/.gnupg as it default home directry and
needs $HOME to resolve "~". As a quick workaround you may export
GNUPGHOME=/home/whereever/.gnupg

The nfiles problem has been fixed in the repo but thre is no released 2.0
version for it, yet. commit is 776bee6d370602ff95e93a4aea6a70005dff9ae6

Thanks Werner.
For normal users home path is set. Output is taken from root user. We will
update home path as needed. We are focusing on nfiles issue currently.

Would you mind to elaborate about "Commit is
776bee6d370602ff95e93a4aea6a70005dff9ae6". I didn't understand this line.

Thanks
Sandeep

That is the commit we have in our source code repository. I copy the patch
below. It is small enough to be applied by hand.

commit 776bee6d370602ff95e93a4aea6a70005dff9ae6
Author: Werner Koch <wk@gnupg.org>
Date: Fri Jan 15 15:32:18 2016 +0100

    common: Cope with AIX problem on number of open files.
    
    * common/exechelp.c: Limit returned value for too hight values.
    --
    
    GnuPG-bug-id: 1778
    
    (backport from master commit 987532b038a2d9b9e76c0de425ee036ca2bffa1b)
    
    Signed-off-by: Werner Koch <wk@gnupg.org>

diff --git a/common/exechelp.c b/common/exechelp.c
index cd9ba7b..6d60b07 100644

• a/common/exechelp.c

+++ b/common/exechelp.c
@@ -21,6 +21,9 @@

#include <stdio.h>
#include <stdlib.h>
+#ifdef HAVE_STDINT_H
+# include <stdint.h>
+#endif
#include <string.h>
#include <errno.h>
#include <assert.h>
@@ -134,6 +137,13 @@ get_max_fds (void)

  if (max_fds == -1)
    max_fds = 256;  /* Arbitrary limit.  */

+ /* AIX returns INT32_MAX instead of a proper value. We assume that
+ this is always an error and use an arbitrary limit. */
+#ifdef INT32_MAX
+ if (max_fds == INT32_MAX)
+ max_fds = 256;
+#endif
+

return max_fds;

}

Werner,

Thanks a lot. I will try to apply the patch.
Can you please let us know if your company is offering enterprise level
support.

Thanks
Sandeep

@werner Can we close this here?