Using Pianoteq version 5.3.0/20150629 now and the bug seems to have magically disappeared.
I am not sure if something was fixed by the Modartt/Pianoteq developers, or in the C++ libs that are shipped with Fedora.
Whoever fixed this, thank you :-)

I need to do more testing to find what shared library/libraries are to blame so that I can send a bugreport to the right people. Or maybe I have to (re)install some library/libraries that are missing or broken.

I have found that the bug (?) not only affects the --help option.
I frequently use Pianoteq on the commandline or in shell scripts to convert batches of pianomusic MIDI files to great sounding WAV files without the need to open the complete GUI interface.
On my current system this works fine if I run the i386 version but gives mysterious errors if I run the amd64 version.

I'll try to do some testing on a Fedora 21 system.

strange. You could try the commands 'file' and 'strace':
Piantoteq is dynamically linked, maybe something is missing on your system:

$ file ./Pianoteq\ 5
./Pianoteq 5: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.26, stripped

Watch the output of strace and how it exits:

$ strace ./Pianoteq\ 5 --help
[...]
write(1, " --play-and-quit   : start playi"..., 72 --play-and-quit   : start playing the midi file, and quit when it ends
) = 72
write(1, "Example of use: Pianoteq --prese"..., 74Example of use: Pianoteq --preset "U4 Small" --midi foo.mid --wav foo.wav
) = 74
exit_group(0)                           = ?
+++ exited with 0 +++

(just an idea)

I tried, on my Fedora 22 x86_64 system, running the i386 binary with the --help commandline option. Now suddenly the help text was displayed normally. So I thought: maybe only the 64bits binary is broken, and the 32bits version is OK?

Then I went to my old 32bits EeePC, also running Fedora 22, and tried Pianoteq with the same --help commandline option there. Now again only the line with the version number and date was shown, just like when using --version. (Off coarse I can not try running the 64bits binary on my 32bits EeePC.)

So until know the only way I can get the --help text to appear is running the i386 version of Pianoteq 5 on my 64 bits Fedora 22 system. But "groovy" replied in this thread it's working fine on 64 bits Debian.

Isn't there anyone who can reproduce my issue, or who can solve this mystery? I'm puzzled.

It looks like the --help option isn't working anymore, where it used to work in previous versions, when running Pianoteq from a Linux Fedora commandline.

--version does work:

$ Pianoteq\ 5 --version

Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com

but --help gives the same output as --version:

$ Pianoteq\ 5 --help

Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com

It's a small issue, but please fix it :-)

Hi,

amd64, Debian:

/Pianoteq\ 5/amd64/Pianoteq\ 5 --help
Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com
Copyright (c) 2015 Modartt.
Options from command-line:
--help            : show this help, and quit
--version         : show current version number and date, and quit
--no-prefs        : start Pianoteq without using any saved preference
--no-audio-prefs  : start Pianoteq with a clean audio/midi configuration
--prefs FILENAME  : stores the preferences in the specified file
--fxp FILENAME    : load an FXP file on startup
--preset NAME     : load a preset on startup
--list-presets    : display the list of all presets
--midimapping NAME: load a midimapping preset on startup
--midi FILENAME   : load a midi file
--wav FILENAME    : export midi file as wav, and quit
--rate FREQ       : change the sample rate for the exported wav
--bit-depth D     : change the bit-depth for the exported wav (16,24 or 32)
--dither ON/OFF   : turn dithering when exporting on or off
--mono            : export the wav file as mono
--headless        : do not show the graphical interface
--fullscreen      : start in fullscreen mode
--play            : immediately start playing the midi file
--play-and-quit   : start playing the midi file, and quit when it ends
Example of use: Pianoteq --preset "U4 Small" --midi foo.mid --wav foo.wav

/Applications/Pianoteq\ 5/Pianoteq\ 5.app/Contents/MacOS/Pianoteq\ 5 --help
Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com
Copyright (c) 2015 Modartt.
Options from command-line:
--help            : show this help, and quit
--version         : show current version number and date, and quit
--no-prefs        : start Pianoteq without using any saved preference
--no-audio-prefs  : start Pianoteq with a clean audio/midi configuration
--prefs FILENAME  : stores the preferences in the specified file
--fxp FILENAME    : load an FXP file on startup
--preset NAME     : load a preset on startup
--list-presets    : display the list of all presets
--midimapping NAME: load a midimapping preset on startup
--midi FILENAME   : load a midi file
--wav FILENAME    : export midi file as wav, and quit
--rate FREQ       : change the sample rate for the exported wav
--bit-depth D     : change the bit-depth for the exported wav (16,24 or 32)
--dither ON/OFF   : turn dithering when exporting on or off
--mono            : export the wav file as mono
--headless        : do not show the graphical interface
--fullscreen      : start in fullscreen mode
--play            : immediately start playing the midi file
--play-and-quit   : start playing the midi file, and quit when it ends
Example of use: Pianoteq --preset "U4 Small" --midi foo.mid --wav foo.wav

--version does work:

$ Pianoteq\ 5 --version

Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com

but --help gives the same output as --version:

$ Pianoteq\ 5 --help

Pianoteq version 5.2.1/20150428 -- http://www.pianoteq.com

It's a small issue, but please fix it :-)