Big thanks to Peter Kunz - specifically when using the CAEN libraries:

>
> After upgrading to the lastes MIDAS version I got the DAQ frontend of my application running by
> changing all compiler directives from cc to g++ and using
>
> #include "mfe.h"
>
> extern HNDLE hDB
> 
>  extern "C" { 
>  #include <CAENComm.h>  
>  }
>
> With these changes everything seems to work fine.
>


K.O.



> > To convert a MIDAS frontend to C++ follow this checklist:
> 
> Pierre A.-A. reminded me that include files for CAEN libraries have  to
> use "extern C" brackets:
> 
> some 3rd party libraries (CAEN, etc) are written in C (or require C linkage),
> if their include files are not C++ compatible (do not have "extern C" brackets
> for all exported symbols), the experiment frontend code must say something like this:
> 
> extern "C" {
> #include "3rd-party-c-library.h"
> }
> 
> Note: "#ifdef cplusplus" is not needed because we already know we are C++, not C.
> 
> K.O.

Ok, so the detail that I missed was that the dummy functions

INT poll_event(INT source[], INT count, BOOL test)
{
   return 1;
};

as shown in some of the older examples, work when you set

INT poll_event(INT source, INT count, BOOL test)
{
   return 1;
};


as a side comment, not all drivers are c++ compatible yet (e.g. mscbvr), so changes needed are small 

> as a side comment, not all drivers are c++ compatible yet (e.g. mscbvr), so changes needed are small 

Right. We recently switched the whole midas to c++, but we could not cover all drivers. Most of them just need some type 
casting to compile under c++. I got already patches from several people which I'm happy to merge in. If you got mscbhvr 
or any other driver compile under c++, please send me the diff.

Stefan

> 
> Ok, so the detail that I missed was that the dummy functions
> 
> INT poll_event(INT source[], INT count, BOOL test)
> {
>    return 1;
> };
> 
> as shown in some of the older examples, work when you set
> 
> INT poll_event(INT source, INT count, BOOL test)
> {
>    return 1;
> };

If you would have read elog:1526 more carefully (point a4) you would have saved yourself a lot of time.

Stefan

To convert a MIDAS frontend to C++ follow this checklist:

a) add #include "mfe.h" after include of midas.h and fix all compilation errors.

NOTE: there should be no "extern C"  brackets around MIDAS include files.

NOTE: Expect to see following problems:

a1) duplicate or mismatched declarations of functions defined in mfe.h
a2) frontend_name and frontend_file_name should be "const char*" instead of "char*"
a3) duplicate "HNDLE hDB" collision with hDB from mfe.c - not sure why it worked before, either use HNDLE hDB from mfe.h or use "extern HNDLE hDB".
a4) poll_event() and interrupt_configure() have "source" as "int[]" instead of "int" (why did this work before?)
a5) use of "extern int frontend_index" instead of get_frontend_index() from mfe.h
a6) bk_create() last argument needs to be cast to (void**)
a7) "bool debug" collides with "debug" from mfe.h (why did this work before?)

b) remove no longer needed "extern C" brackets around mfe related code. Ideally there should be no "extern C" brackets anywhere.

c) in the Makefile, change CC=gcc to CC=g++ for compiling and linking everything as C++

c1) fix all compilation problems. most valid C code will compile as valid C++, but there is some known trouble:
- return value of malloc() & co needs to be cast to the correct data type: "char* s = (char*)malloc(...)"
- some C++ compilers complain about mismatch between signed and unsigned values

If you need help with converting your frontend from C to C++, I will be most happy
to assist you - post your compiler error messages to this forum or email them to me privately.

Good luck,
K.O.

> To convert a MIDAS frontend to C++ follow this checklist:

Pierre A.-A. reminded me that include files for CAEN libraries have  to
use "extern C" brackets:

some 3rd party libraries (CAEN, etc) are written in C (or require C linkage),
if their include files are not C++ compatible (do not have "extern C" brackets
for all exported symbols), the experiment frontend code must say something like this:

extern "C" {
#include "3rd-party-c-library.h"
}

Note: "#ifdef cplusplus" is not needed because we already know we are C++, not C.

K.O.

I am moving our fe code to c++ midas with cmake. I did encounter your a) problems.

How do I solve mismatched declarations in the mfe (or other places in the midas code)? It is having issues with the midas defined BOOL/... types. This 
is what I get for a minimal scfe:

[ 12%] Building CXX object CMakeFiles/sc_fe_mini.dir/sc_fe_mini.cpp.o
[ 25%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/class/hv.cxx.o
[ 37%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/class/multi.cxx.o
[ 50%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/device/nulldev.cxx.o
[ 62%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/bus/null.cxx.o
[ 75%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/device/mscbdev.cxx.o
[ 87%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/mscb/src/mscb.cxx.o
[100%] Linking CXX executable sc_fe_mini
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `_readout_thread':
/home/frederik/packages/midas/src/mfe.cxx:1271: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `check_polled_events':
/home/frederik/packages/midas/src/mfe.cxx:1601: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/src/mfe.cxx:1643: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `readout_enable(unsigned int)':
/home/frederik/packages/midas/src/mfe.cxx:1158: undefined reference to `interrupt_configure(int, int, long)'
/home/frederik/packages/midas/src/mfe.cxx:1156: undefined reference to `interrupt_configure(int, int, long)'
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `initialize_equipment':
/home/frederik/packages/midas/src/mfe.cxx:614: undefined reference to `interrupt_configure(int, int, long)'
/home/frederik/packages/midas/src/mfe.cxx:649: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `scheduler':
/home/frederik/packages/midas/src/mfe.cxx:1890: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/src/mfe.cxx:1932: undefined reference to `poll_event(int, int, unsigned int)'
/home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `main':
/home/frederik/packages/midas/src/mfe.cxx:2701: undefined reference to `interrupt_configure(int, int, long)'
/home/frederik/packages/midas/src/mfe.cxx:2702: undefined reference to `interrupt_configure(int, int, long)'
collect2: error: ld returned 1 exit status
make[2]: *** [sc_fe_mini] Error 1
make[1]: *** [CMakeFiles/sc_fe_mini.dir/all] Error 2
make: *** [all] Error 2


This is my cmakelists for my user code:

#
# cmake for the muX software
#
cmake_minimum_required(VERSION 3.3)

project(muX)

#
# find installations
#
set(MIDAS_DIR $ENV{MIDASSYS})
message("MIDAS dir: " ${MIDAS_DIR})

#
# set directories
#
set(MIDASBUILD_DIR ${MIDAS_DIR}/build)
set(MIDASINCLUDE_DIR ${MIDAS_DIR}/include)
set(MXML_DIR ${MIDAS_DIR}/mxml)
set(MSCB_DIR ${MIDAS_DIR}/mscb)
set(DRV_DIR ${MIDAS_DIR}/drivers)


#
# drivers, libs
#
set(DRIVERS
    ${MIDAS_DIR}/drivers/class/hv
    ${MIDAS_DIR}/drivers/class/multi
    ${MIDAS_DIR}/drivers/device/nulldev
    ${MIDAS_DIR}/drivers/bus/null
)
set(MIDASLIB ${MIDASBUILD_DIR}/libmidas.a)
set(FELIB ${MIDASBUILD_DIR}/libmfe.a)

#
# sc_fe
#
add_executable(sc_fe_mini
        sc_fe_mini.cpp
        ${DRIVERS}
        ${MIDAS_DIR}/drivers/device/mscbdev
        ${MIDAS_DIR}/mscb/src/mscb)

target_include_directories(sc_fe_mini PRIVATE ${DRV_DIR} ${MIDAS_DIR}/mscb/include ${MIDAS_DIR}/include)
target_link_libraries(sc_fe_mini ${LIBS} ${MIDASLIB} ${FELIB} rt pthread util)



I seem to be able to compile the current midas distributions, including the scfe frontend



> To convert a MIDAS frontend to C++ follow this checklist:
> 
> a) add #include "mfe.h" after include of midas.h and fix all compilation errors.
> 
> NOTE: there should be no "extern C"  brackets around MIDAS include files.
> 
> NOTE: Expect to see following problems:
> 
> a1) duplicate or mismatched declarations of functions defined in mfe.h
> a2) frontend_name and frontend_file_name should be "const char*" instead of "char*"
> a3) duplicate "HNDLE hDB" collision with hDB from mfe.c - not sure why it worked before, either use HNDLE hDB from mfe.h or use "extern HNDLE hDB".
> a4) poll_event() and interrupt_configure() have "source" as "int[]" instead of "int" (why did this work before?)
> a5) use of "extern int frontend_index" instead of get_frontend_index() from mfe.h
> a6) bk_create() last argument needs to be cast to (void**)
> a7) "bool debug" collides with "debug" from mfe.h (why did this work before?)
> 
> b) remove no longer needed "extern C" brackets around mfe related code. Ideally there should be no "extern C" brackets anywhere.
> 
> c) in the Makefile, change CC=gcc to CC=g++ for compiling and linking everything as C++
> 
> c1) fix all compilation problems. most valid C code will compile as valid C++, but there is some known trouble:
> - return value of malloc() & co needs to be cast to the correct data type: "char* s = (char*)malloc(...)"
> - some C++ compilers complain about mismatch between signed and unsigned values
> 
> If you need help with converting your frontend from C to C++, I will be most happy
> to assist you - post your compiler error messages to this forum or email them to me privately.
> 
> Good luck,
> K.O.

Did you include mfe.h as written in elog:1526 ?

Stefan

> Did you include mfe.h as written in elog:1526 ?
> 
> Stefan


Yes I did

this is my include 

#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <math.h>
#include <pthread.h>


#include "midas.h"
#include "mscb.h"
#include "multi.h"
#include "mscbdev.h"
#include "mfe.h"

(I attach my dummy fe)

What confuses me is that I can compile examples/experiment/ if I copy that to a 
fresh dir.

I also copied the CMakeLists from the example:

#
# cmake for the muX software
#
cmake_minimum_required(VERSION 3.3)

project(muX)

#
# find midas installation, from CMakeLists in examples/experiment
#
set(MIDAS_DIR $ENV{MIDASSYS})
message("MIDAS dir: " ${MIDAS_DIR})
if (NOT EXISTS $ENV{MIDASSYS})
  message(FATAL_ERROR "Environment variable $MIDASSYS not defined, aborting.")
endif()

set(INC_PATH ${MIDAS_DIR}/include ${MIDAS_DIR}/mxml ${MIDAS_DIR}/mscb/include 
${MIDAS_DIR}/drivers/class ${MIDAS_DIR}/drivers/device)
link_directories($ENV{MIDASSYS}/lib)

# enable certain compile warnings
add_compile_options(-Wall -Wformat=2 -Wno-format-nonliteral -Wno-strict-
aliasing -Wuninitialized -Wno-unused-function)

set(LIBS -lpthread -lutil -lrt) 


add_executable(sc_fe_mini sc_fe_mini.cpp)
target_include_directories(sc_fe_mini PRIVATE ${INC_PATH})
target_link_libraries(sc_fe_mini mfe midas ${LIBS})

Have you left any "extern C" in your frontend program or in any of the used header file. Seems 
like the linker cannot find the poll_event in your frontend code. If it's there, but it's compiled 
with C calling (instead of C++), the name mangling causes it to be invisible to the linker. That 
usually happens if there is somewhere

extern C {
  INT poll_event();
  ... 
}

while it is NOT defined as "extern C" in mfe.h which is used by mfe.cxx.

Stefan

> > Did you include mfe.h as written in elog:1526 ?
> > 
> > Stefan
> 
> 
> Yes I did
> 
> this is my include 
> 
> #include <stdio.h>
> #include <string.h>
> #include <assert.h>
> #include <math.h>
> #include <pthread.h>
> 
> 
> #include "midas.h"
> #include "mscb.h"
> #include "multi.h"
> #include "mscbdev.h"
> #include "mfe.h"
> 
> (I attach my dummy fe)
> 
> What confuses me is that I can compile examples/experiment/ if I copy that to a 
> fresh dir.
> 
> I also copied the CMakeLists from the example:
> 
> #
> # cmake for the muX software
> #
> cmake_minimum_required(VERSION 3.3)
> 
> project(muX)
> 
> #
> # find midas installation, from CMakeLists in examples/experiment
> #
> set(MIDAS_DIR $ENV{MIDASSYS})
> message("MIDAS dir: " ${MIDAS_DIR})
> if (NOT EXISTS $ENV{MIDASSYS})
>   message(FATAL_ERROR "Environment variable $MIDASSYS not defined, aborting.")
> endif()
> 
> set(INC_PATH ${MIDAS_DIR}/include ${MIDAS_DIR}/mxml ${MIDAS_DIR}/mscb/include 
> ${MIDAS_DIR}/drivers/class ${MIDAS_DIR}/drivers/device)
> link_directories($ENV{MIDASSYS}/lib)
> 
> # enable certain compile warnings
> add_compile_options(-Wall -Wformat=2 -Wno-format-nonliteral -Wno-strict-
> aliasing -Wuninitialized -Wno-unused-function)
> 
> set(LIBS -lpthread -lutil -lrt) 
> 
> 
> add_executable(sc_fe_mini sc_fe_mini.cpp)
> target_include_directories(sc_fe_mini PRIVATE ${INC_PATH})
> target_link_libraries(sc_fe_mini mfe midas ${LIBS})

Can you post the exact command that cmake executes to link sc_fe_mini (with make VERBOSE=1)?

I have noticed similar linking problems that depended on the order when linking. In my case, it 
compiled when "-lpthread -lutil -lrt" were at the end of the command, but not before mfe.o and 
libmidas.a. Unfortunately I haven't found a way to tell cmake the "correct" order of the link 
libraries.

Maybe this can be fixed by adding midas as a subdirectory in your cmake project and just linking 
against the "mfe" target instead of libmfe.a.

> How do I solve mismatched declarations in the mfe (or other places in the midas code)?

I run into such problems all the time. My solution? I grep for the function name in my code and in the header file,
then look very carefully at the definition to confirm that all the argument declarations are the same in both
places. Sometimes my eyes do not see the difference and I ask for a "second pair of eyes".

In your case, you have a mismatch between functions in mfe.h and in your frontend. The difference
is "int source" in mfe.h and "int source[]" in your code.

Because C++ permits functions with identical namesm but different arguments, the compiler thinks
you did this on purpose and does not complain. Later, of course, the linker bombs,
but all it can report at this stage, is what you see "function not found"... Then you grep your code
for the missing function, check arguments, rinse, repeat.

Before C++, the C compiler would probably had complained about the mismatch, except that MIDAS
did not have an mfe.h header file definitions for all this stuff until just now, so again, the mismatch would
have gone unnoticed, unfixed.

K.O.



> It is having issues with the midas defined BOOL/... types. This 
> is what I get for a minimal scfe:
> 
> [ 12%] Building CXX object CMakeFiles/sc_fe_mini.dir/sc_fe_mini.cpp.o
> [ 25%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/class/hv.cxx.o
> [ 37%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/class/multi.cxx.o
> [ 50%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/device/nulldev.cxx.o
> [ 62%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/bus/null.cxx.o
> [ 75%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/drivers/device/mscbdev.cxx.o
> [ 87%] Building CXX object CMakeFiles/sc_fe_mini.dir/home/frederik/packages/midas/mscb/src/mscb.cxx.o
> [100%] Linking CXX executable sc_fe_mini
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `_readout_thread':
> /home/frederik/packages/midas/src/mfe.cxx:1271: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `check_polled_events':
> /home/frederik/packages/midas/src/mfe.cxx:1601: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/src/mfe.cxx:1643: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `readout_enable(unsigned int)':
> /home/frederik/packages/midas/src/mfe.cxx:1158: undefined reference to `interrupt_configure(int, int, long)'
> /home/frederik/packages/midas/src/mfe.cxx:1156: undefined reference to `interrupt_configure(int, int, long)'
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `initialize_equipment':
> /home/frederik/packages/midas/src/mfe.cxx:614: undefined reference to `interrupt_configure(int, int, long)'
> /home/frederik/packages/midas/src/mfe.cxx:649: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `scheduler':
> /home/frederik/packages/midas/src/mfe.cxx:1890: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/src/mfe.cxx:1932: undefined reference to `poll_event(int, int, unsigned int)'
> /home/frederik/packages/midas/build/libmfe.a(mfe.cxx.o): In function `main':
> /home/frederik/packages/midas/src/mfe.cxx:2701: undefined reference to `interrupt_configure(int, int, long)'
> /home/frederik/packages/midas/src/mfe.cxx:2702: undefined reference to `interrupt_configure(int, int, long)'
> collect2: error: ld returned 1 exit status
> make[2]: *** [sc_fe_mini] Error 1
> make[1]: *** [CMakeFiles/sc_fe_mini.dir/all] Error 2
> make: *** [all] Error 2
> 
> 
> This is my cmakelists for my user code:
> 
> #
> # cmake for the muX software
> #
> cmake_minimum_required(VERSION 3.3)
> 
> project(muX)
> 
> #
> # find installations
> #
> set(MIDAS_DIR $ENV{MIDASSYS})
> message("MIDAS dir: " ${MIDAS_DIR})
> 
> #
> # set directories
> #
> set(MIDASBUILD_DIR ${MIDAS_DIR}/build)
> set(MIDASINCLUDE_DIR ${MIDAS_DIR}/include)
> set(MXML_DIR ${MIDAS_DIR}/mxml)
> set(MSCB_DIR ${MIDAS_DIR}/mscb)
> set(DRV_DIR ${MIDAS_DIR}/drivers)
> 
> 
> #
> # drivers, libs
> #
> set(DRIVERS
>     ${MIDAS_DIR}/drivers/class/hv
>     ${MIDAS_DIR}/drivers/class/multi
>     ${MIDAS_DIR}/drivers/device/nulldev
>     ${MIDAS_DIR}/drivers/bus/null
> )
> set(MIDASLIB ${MIDASBUILD_DIR}/libmidas.a)
> set(FELIB ${MIDASBUILD_DIR}/libmfe.a)
> 
> #
> # sc_fe
> #
> add_executable(sc_fe_mini
>         sc_fe_mini.cpp
>         ${DRIVERS}
>         ${MIDAS_DIR}/drivers/device/mscbdev
>         ${MIDAS_DIR}/mscb/src/mscb)
> 
> target_include_directories(sc_fe_mini PRIVATE ${DRV_DIR} ${MIDAS_DIR}/mscb/include ${MIDAS_DIR}/include)
> target_link_libraries(sc_fe_mini ${LIBS} ${MIDASLIB} ${FELIB} rt pthread util)
> 
> 
> 
> I seem to be able to compile the current midas distributions, including the scfe frontend
> 
> 
> 
> > To convert a MIDAS frontend to C++ follow this checklist:
> > 
> > a) add #include "mfe.h" after include of midas.h and fix all compilation errors.
> > 
> > NOTE: there should be no "extern C"  brackets around MIDAS include files.
> > 
> > NOTE: Expect to see following problems:
> > 
> > a1) duplicate or mismatched declarations of functions defined in mfe.h
> > a2) frontend_name and frontend_file_name should be "const char*" instead of "char*"
> > a3) duplicate "HNDLE hDB" collision with hDB from mfe.c - not sure why it worked before, either use HNDLE hDB from mfe.h or use "extern HNDLE hDB".
> > a4) poll_event() and interrupt_configure() have "source" as "int[]" instead of "int" (why did this work before?)
> > a5) use of "extern int frontend_index" instead of get_frontend_index() from mfe.h
> > a6) bk_create() last argument needs to be cast to (void**)
> > a7) "bool debug" collides with "debug" from mfe.h (why did this work before?)
> > 
> > b) remove no longer needed "extern C" brackets around mfe related code. Ideally there should be no "extern C" brackets anywhere.
> > 
> > c) in the Makefile, change CC=gcc to CC=g++ for compiling and linking everything as C++
> > 
> > c1) fix all compilation problems. most valid C code will compile as valid C++, but there is some known trouble:
> > - return value of malloc() & co needs to be cast to the correct data type: "char* s = (char*)malloc(...)"
> > - some C++ compilers complain about mismatch between signed and unsigned values
> > 
> > If you need help with converting your frontend from C to C++, I will be most happy
> > to assist you - post your compiler error messages to this forum or email them to me privately.
> > 
> > Good luck,
> > K.O.

I add the following to makefile and try to treat Darwin as FreeBSD/Linux.
But I failed.
============ 
#-----------------------
# This is for MacOS X
#
ifeq ($(OSTYPE), Darwin)
CC = gcc
OS_DIR = Darwin
OSFLAGS = -DOS_DARWIN -DOS_LINUX
LIBS = -lbsd -lcompat
SPECIFIC_OS_PRG =
endif
============

I got the following errors:
=============
gcc -c -g -O2 -Wall -Iinclude -Idrivers -LDarwin/lib -DINCLUDE_FTPLIB  
-DOS_DARWIN -DOS_FREEBSD -o Darwin/lib/midas.o src/midas.c
In file included from include/midasinc.h:45,
                 from include/msystem.h:114,
                 from src/midas.c:623:
/usr/include/string.h:112: error: conflicting types for `strlcat'
include/midas.h:1701: error: previous declaration of `strlcat'
/usr/include/string.h:113: error: conflicting types for `strlcpy'
include/midas.h:1700: error: previous declaration of `strlcpy'
In file included from include/msystem.h:114,
                 from src/midas.c:623:
include/midasinc.h:161:21: sys/vfs.h: No such file or directory
include/midasinc.h:164:17: pty.h: No such file or directory
src/midas.c:780: error: conflicting types for `dbg_malloc'
include/midas.h:1478: error: previous declaration of `dbg_malloc'
src/midas.c:817: error: conflicting types for `dbg_calloc'
include/midas.h:1479: error: previous declaration of `dbg_calloc'
src/midas.c:858: error: conflicting types for `strlcpy'
/usr/include/string.h:113: error: previous declaration of `strlcpy'
src/midas.c:892: error: conflicting types for `strlcat'
/usr/include/string.h:112: error: previous declaration of `strlcat'
gmake: *** [Darwin/lib/midas.o] Error 1
==========

Could anyone give me some hints. Thanks!

The current (cvs) version of MIDAS should build on Mac OS X right out of the
box- I fixed all the problems you report back in February(?)- see the macosx
thread in this forum. A few weeks ago I verified that it still compiles on Mac
OS 10.3.4. The Mac OS port received minimal testing- I checked that "odbedit"
and "mhttpd" run, that's about it. K.O.

> I add the following to makefile and try to treat Darwin as FreeBSD/Linux.
> But I failed.
> ============ 
> #-----------------------
> # This is for MacOS X
> #
> ifeq ($(OSTYPE), Darwin)
> CC = gcc
> OS_DIR = Darwin
> OSFLAGS = -DOS_DARWIN -DOS_LINUX
> LIBS = -lbsd -lcompat
> SPECIFIC_OS_PRG =
> endif
> ============
> 
> I got the following errors:
> =============
> gcc -c -g -O2 -Wall -Iinclude -Idrivers -LDarwin/lib -DINCLUDE_FTPLIB  
> -DOS_DARWIN -DOS_FREEBSD -o Darwin/lib/midas.o src/midas.c
> In file included from include/midasinc.h:45,
>                  from include/msystem.h:114,
>                  from src/midas.c:623:
> /usr/include/string.h:112: error: conflicting types for `strlcat'
> include/midas.h:1701: error: previous declaration of `strlcat'
> /usr/include/string.h:113: error: conflicting types for `strlcpy'
> include/midas.h:1700: error: previous declaration of `strlcpy'
> In file included from include/msystem.h:114,
>                  from src/midas.c:623:
> include/midasinc.h:161:21: sys/vfs.h: No such file or directory
> include/midasinc.h:164:17: pty.h: No such file or directory
> src/midas.c:780: error: conflicting types for `dbg_malloc'
> include/midas.h:1478: error: previous declaration of `dbg_malloc'
> src/midas.c:817: error: conflicting types for `dbg_calloc'
> include/midas.h:1479: error: previous declaration of `dbg_calloc'
> src/midas.c:858: error: conflicting types for `strlcpy'
> /usr/include/string.h:113: error: previous declaration of `strlcpy'
> src/midas.c:892: error: conflicting types for `strlcat'
> /usr/include/string.h:112: error: previous declaration of `strlcat'
> gmake: *** [Darwin/lib/midas.o] Error 1
> ==========
> 
> Could anyone give me some hints. Thanks!

> The current (cvs) version of MIDAS should build on Mac OS X right out of the
> box- I fixed all the problems you report back in February(?)- see the macosx
> thread in this forum. A few weeks ago I verified that it still compiles on Mac
> OS 10.3.4. The Mac OS port received minimal testing- I checked that "odbedit"
> and "mhttpd" run, that's about it. K.O.
> 

Thanks a lot. But I cannot checkout module:
------------
01:52:16: pc2075.psi.ch: Operation timed out
01:52:16: cvs [checkout aborted]: end of file from server (consult above
messages if any)
------------

Could anybody add download tar package in the WWW interface of CVS repository.
I know the original CGI script has such a feature. Thanks.

P.S.
I use these commands to checkout:
   cvs -e ssh -d :ext:cvs@midas.psi.ch:/usr/local/cvsroot checkout midas
   cvs -e ssh -d :ext:cvs@midas.psi.ch:/usr/local/cvsroot update

> Thanks a lot. But I cannot checkout module:
> ------------
> 01:52:16: pc2075.psi.ch: Operation timed out
> 01:52:16: cvs [checkout aborted]: end of file from server (consult above
> messages if any)
> ------------

Should work fine, just tried from outside PSI. Please check again.

> Could anybody add download tar package in the WWW interface of CVS repository.
> I know the original CGI script has such a feature. Thanks.

The tar package is only done for a new release (which will happen in the next days
BTW), so http://midas.psi.ch/download/tar/ contains the most recent packages. Upon
request I make a midas-snapshot.tar.gz, but since there will be a 1.9.4 soon, it's
maybe not necessary right now.

> 
> Should work fine, just tried from outside PSI. Please check again.

Unfortunately, I still encounter the same problem. 
---
pc2075.psi.ch: Operation timed out
cvs [checkout aborted]: end of file from server (consult above messages if any)
---

I am in LNS-INFN (Italy), i.e., I am outside PSI. So ... what's the problem? I try to
ping the host, and it is reachable:
--------
[exaos@exaos cvsnew]$ ping midas.psi.ch
PING pc2075.psi.ch (129.129.228.23): 56 data bytes
64 bytes from 129.129.228.23: icmp_seq=0 ttl=50 time=67.237 ms
64 bytes from 129.129.228.23: icmp_seq=1 ttl=50 time=64.202 ms
64 bytes from 129.129.228.23: icmp_seq=2 ttl=50 time=56.278 ms
...
--------
Is it the problem of firewall? I am not sure. So strange.

> 
> The tar package is only done for a new release (which will happen in the next days
> BTW), so http://midas.psi.ch/download/tar/ contains the most recent packages. Upon
> request I make a midas-snapshot.tar.gz, but since there will be a 1.9.4 soon, it's
> maybe not necessary right now.

Waiting for the new release ...

Reading an FADC buffer often needs large buffer size, especially while several
FADCs work together. I want to know how large a bank32 can support.

> Reading an FADC buffer often needs large buffer size, especially while several
> FADCs work together. I want to know how large a bank32 can support.

The "32" in bank32 means 32-bits, so the bank holds 2^32=4 GBytes, hope that is enough for your ADC. 
The "normal" bank has only a 16-bit header, so it can hold only 64 kBytes. But for small banks, the overhead 
is therefore smaller.

> Reading an FADC buffer often needs large buffer size, especially while several
> FADCs work together. I want to know how large a bank32 can support.

Limitations in order:

- bank32 size is limited to a 32 bit integer size (about 4000 Gbytes)
- bank size is limited by event size
- event size in a midas mfe.c based frontend is limited to the value of
max_event_size set by the user
- maximum event size that can go through the MIDAS event buffer system is limited
to ODB value /Experiment/MAX_EVENT_SIZE (MAX_EVENT_SIZE in midas.h does not do
anything now)
- maximum event size is limited to *half* the size of the SYSTEM shared memory
event buffer (or any other buffers that the event has to go through)
- default size of the SYSTEM buffer is 8 Mbytes set by ODB /Experiment/Buffer
sizes/SYSTEM. This limits maximum event size to about 4 Mbytes.
- size of SYSTEM buffer can be increased to arbitrary size, but in practice no
bigger than the amount of computer physical memory minus space needed for running
the frontend program and the mlogger, which also allocate buffer space to hold 1
event of maximum size.

So for a computer with 8 Gbytes of RAM, you can make the SYSTEM buffer size 4
GBytes, set ODB MAX_EVENT_SIZE to 1 Gbyte, and in theory, you should be able to
write 1 Gbyte events from your frontend to disk.

In practice, I think the biggest events I have seen go through a MIDAS system are
non-compressed waveforms in the T2K/ND280 FGD and TPC detectors, about 4 Mbytes of
data per event.

Other considerations (rules of thumb):

1) the SYSTEM event buffer should be big enough to hold 10-100 events.
2) the SYSTEM event buffer should be big enough to hold about 5-10 seconds of data
- i.e. if your event size is 1 Mbyte and data rate is 1 Hz, 10 seconds of data
will be 1Mbyte*1Hz*10sec = 10 Mbytes.

This is because the SYSTEM buffer decouples the real-time activity of the frontend
program from non-real-time activity of writing data to storage devices.

K.O.