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#71
Beginner questions / Working Directory woes
Last post by PhilG57 - July 02, 2026, 04:16:44 PMI have a Windows project with multiple versions kept in separate directories. I edit and update in one directory and when those changes look and test good, I move them to another, separate, directory of more stable code.
In any of those project versions, when I open a file with GetOpenFileName(), the directory shown from which to select a file to open, is the directory last used by Pelles C. For example, in the GetOpenFileName() dialog, if I change to a different directory and select a file from there, that directory becomes the 'default' location shown by GetOpenFileName() the next time it is called.
So far, so good I think. What I don't understand is with the opening of a new or different project using the same instance of Pelles C, or especially with a new clean instance of Pelles C, why does the default GetOpenFileName() use what I selected before and not the default directory listed in my project's options. As part of the initialization code, I do execute a GetCurrentDirectory() followed by a SetCurrentDirectory() to no avail.
As always, thanks in advance.
In any of those project versions, when I open a file with GetOpenFileName(), the directory shown from which to select a file to open, is the directory last used by Pelles C. For example, in the GetOpenFileName() dialog, if I change to a different directory and select a file from there, that directory becomes the 'default' location shown by GetOpenFileName() the next time it is called.
So far, so good I think. What I don't understand is with the opening of a new or different project using the same instance of Pelles C, or especially with a new clean instance of Pelles C, why does the default GetOpenFileName() use what I selected before and not the default directory listed in my project's options. As part of the initialization code, I do execute a GetCurrentDirectory() followed by a SetCurrentDirectory() to no avail.
As always, thanks in advance.
#72
Announcements / CMake 4.4.0 Supports Pelles C
Last post by Robert - July 01, 2026, 04:08:26 AMCMake 4.4.0 Supports Pelles C.
https://gitlab.kitware.com/cmake/cmake/-/work_items/21536
DownLoad here:
https://cmake.org/download/
https://gitlab.kitware.com/cmake/cmake/-/work_items/21536
DownLoad here:
https://cmake.org/download/
#73
Beginner questions / Re: Importing a function from ...
Last post by jm - June 30, 2026, 05:27:04 PMQuote from: TimoVJL on June 30, 2026, 12:51:55 PMJust Enable Microsoft extensions to remove warningGood to know that, thanks for your help. The F1 help is great too, for anyone else new to Pelles C.
#74
Beginner questions / Re: Importing a function from ...
Last post by TimoVJL - June 30, 2026, 12:51:55 PMQuote...\MyDLL\pelles\pelles.c(3): warning #2203: Function 'my_function' can't be __stdcall, changed to __cdecl.Just Enable Microsoft extensions to remove warning
#75
Beginner questions / Re: Importing a function from ...
Last post by jm - June 28, 2026, 03:35:40 PMIt's all fixed, thank you very much for your help. I realise my ridiculous mistake now — while I can put the .LIB in a separate library folder as you pointed out, the .DLL at least has to be in the path when the executable runs.
Incidentally, the float return was also my error, it wasn't a problem at all in the end. My DLL is in fact 64-bit code, but if I change the calling convention to float __stdcall, it warns me :
...\MyDLL\pelles\pelles.c(3): warning #2203: Function 'my_function' can't be __stdcall, changed to __cdecl.
Interesting to see that.
Incidentally, the float return was also my error, it wasn't a problem at all in the end. My DLL is in fact 64-bit code, but if I change the calling convention to float __stdcall, it warns me :
...\MyDLL\pelles\pelles.c(3): warning #2203: Function 'my_function' can't be __stdcall, changed to __cdecl.
Interesting to see that.
#76
Beginner questions / Re: Importing a function from ...
Last post by TimoVJL - June 28, 2026, 12:39:51 PMFor libraries, use Project options -> General -> Folders -> Libraries
If a your JDL.DLL exports function, a calling convention had to know at least in x86, as x64 have only one calling convention.
like:
If a your JDL.DLL exports function, a calling convention had to know at least in x86, as x64 have only one calling convention.
like:
Code Select
float __cdecl myfunc(float); // _myfuncorCode Select
float __stdcall myfunc(float); // _myfunc@4 #77
Beginner questions / Re: Importing a function from ...
Last post by jm - June 28, 2026, 11:54:29 AMMany thanks indeed Vortex, that worked very well. As I'd expected, it was necessary for me to put my .DLL and .LIB into the project's folder and also go to Project — Project options — Linker, then add the .LIB filename to the Library and Object Files box.
Is there a way to inform the compiler/linker that the .DLL and .LIB files are in a specific path outside the project folder? I tried specifying the full path of the .LIB but it wouldn't compile, presumbly because it also requires the path to the .DLL. I couldn't find a way of doing that.
I wasn't able to return a float or double with the expected value, but I expect that's due to calling methods, so I need to experiment further with that.
Is there a way to inform the compiler/linker that the .DLL and .LIB files are in a specific path outside the project folder? I tried specifying the full path of the .LIB but it wouldn't compile, presumbly because it also requires the path to the .DLL. I couldn't find a way of doing that.
I wasn't able to return a float or double with the expected value, but I expect that's due to calling methods, so I need to experiment further with that.
#78
Beginner questions / Re: Importing a function from ...
Last post by Vortex - June 27, 2026, 10:02:33 PMHi jm,
The .h file, the header file contains the prototypes of the functions exported by your DLL. Strictly, you don't need a header file. All what you need is to translate correctly your function prototypes in that language to C.
As an example, consider the source code of this simple FreeBASIC DLL named testdll.dll :
Pelles C code with the function prototypes :
The .h file, the header file contains the prototypes of the functions exported by your DLL. Strictly, you don't need a header file. All what you need is to translate correctly your function prototypes in that language to C.
As an example, consider the source code of this simple FreeBASIC DLL named testdll.dll :
Code Select
Function sum Cdecl Alias "sum" (Byval x As Integer, Byval y As Integer) As Integer Export
Return(x+y)
End Function
Function subs Cdecl Alias "subs" (Byval x As Integer, Byval y As Integer) As Integer Export
Return(x-y)
End Function
Pelles C code with the function prototypes :
Code Select
#include <stdio.h>
extern int __cdecl sum(int x,int y);
extern int __cdecl subs(int x,int y);
int main(void)
{
printf("70 + 30 = %d\n",sum(70,30));
printf("70 - 30 = %d",subs(70,30));
return 0;
}
#79
Beginner questions / Importing a function from a DL...
Last post by jm - June 27, 2026, 07:50:22 PMThis is purely a research exercise on my part with limited knowledge. I'd be grateful if someone could tell me if there's a way in which I can import a function from a Windows DLL that I created using a non-C language compiler on Windows.
The other language compiler has understandably given me only a .DLL and a .LIB but the examples I've seen, where a DLL is used within C, appear to show a .H header is needed. What should I create in the .H file, or is there another way?
The DLL I created is called JDL.DLL and it contains a function called myfunction() to accept a float value and return the result also as a float. Can anyone help with this please, thanks.
The other language compiler has understandably given me only a .DLL and a .LIB but the examples I've seen, where a DLL is used within C, appear to show a .H header is needed. What should I create in the .H file, or is there another way?
The DLL I created is called JDL.DLL and it contains a function called myfunction() to accept a float value and return the result also as a float. Can anyone help with this please, thanks.
#80
Work in progress / Re: New Task Schedule 2.0 exam...
Last post by John Z - June 26, 2026, 04:23:26 AMHere is plain C working code to schedule a task. It is implemented in my upcoming version of the calendar which already has a vbs task scheduler and a powershell task scheduler, now has a C task scheduler...covering my basis 
I like to mention that it uses TimoVJL's Variant setup (which I did not know how to do) THANKS Timo!
Example inputs are also provided within the code at various places. Look for //EX:
Source code attached . . .
It is a complete working 'one time' scheduler, just created the names structure and fill in that should be most all of the work.
If needing a daily or some repeated schedule look at TimoVJL's code near the top of this stream, he's done it.
John Z
See next post -
I like to mention that it uses TimoVJL's Variant setup (which I did not know how to do) THANKS Timo!
Example inputs are also provided within the code at various places. Look for //EX:
It is a complete working 'one time' scheduler, just created the names structure and fill in that should be most all of the work.
If needing a daily or some repeated schedule look at TimoVJL's code near the top of this stream, he's done it.
John Z
See next post -