I wrote a demo using libpq to connect to a PostgreSQL database.
I tried to connect the C file to PostgreSQL by including
#include <libpq-fe.h>
after I added the paths into system variables I:\Program Files\PostgreSQL\12\lib as well as to I:\Program Files\PostgreSQL\12\include and compiled with this command:
gcc -Wall -Wextra -m64 -I "I:\Program Files\PostgreSQL\12\include" -L "I:\Program Files\PostgreSQL\12\lib" testpsql.c -lpq -o testpsql
It first raised three errors, like
libssl-1_1-x64.dll is missing
libintl-8.dll was missing
libcrypto-1_1-x64.dll was missing
After I downloaded these three files and put them into I:\Program Files\PostgreSQL\12\lib, and compiled it again, it shows the error
The application was unable to start correctly (0xc0150002)
when I type testpsql. But if I type ./testpsql on git bash, it works. Anyone can please tell me why?
The code that I used was the first example from here.
Environment: PostgreSQL 12, Windows 10, MinGW64
“Download the DLL files” sounds dangerous. From where?
I would get rid of these files again. Since you probably don't reference these libraries from your code, it must be the dependencies of libpq.dll and are probably found in I:\Program Files\PostgreSQL\12\bin (if you used the EDB installer).
The problem is probably that you the PATH environment variable is different in git bash and in cmd.exe, and in the latter case not all required shared libraries can be found on the PATH. The solution is to change the PATH so that it includes all DLL files the executable requires, not to start copying around files.
It is probably enough to include I:\Program Files\PostgreSQL\12\bin in the PATH. To resolve missing dependencies, use a tool like dependency walker or this replacement.
Disclaimer: I'm no software engineer or programmer. I just know enough to get myself in trouble. Please forgive any misused or inaccurate terms.
I'm currently trying to test my HDF5 installation using the in-built Example test scripts. These are organised by CMake and compiled by gcc (MinGW and MinGW-w64). When I go to execute the test script:
ctest -S HDF518_Examples.cmake -C Release -V -O test.log
I'm met with pages and pages of errors, the core of these being:
mingw32-make.exe[2]: *** No rule to make target 'C:/aroot/stage/Library/lib/z.lib', needed by 'bin/h5ex_d_compact.exe'. Stop.
From my hours of trying to fix this on my own, I've been able to work out that z.lib is a library file part of the ZLIB library, ubiquitous these days. I also know that I have at least one copy of this particular file in my Anaconda directory under /Library/lib/.
I have two questions:
1) How can I get CMake or MinGW to recognize where this file is, and hence stop this error? Is there an environment variable I can set, or a config file I can modify?
2) As an aside, where did this path come from? There is no C:/aroot/ directory on my computer. I've also been unable to find any generators for this path in any of the CMake, HDF5, or MinGW files. So why is CMake pointing to this faux-directory?
Any help would be appreciated.
I use ENVIRONMENT PATH in set_tests_properties to specify the dependent external libraries.
set_tests_properties(${Testname} PROPERTIES ENVIRONMENT
PATH=${/your/zlib/location}
WORKING_DIRECTORY "${/your/working/directory}/")
I am trying to run a C compiler with Cython in a 64-bit Windows 7 platform.
After having various problems with the C compilers from Visual studio and MinGW32, I tried to install MinGW_w64. I did the following steps :
-I downloaded and extracted winbuilds from http://mingw-w64.org/doku.php/download/win-builds, and I selected the Base GCC package with C support.
-I added C:\PATH_TO_WINBUILDS and C:\PATH_TO_WINBUILDS\bin in the PATH Windows environment variable.
-I wrote helloworld.c, a very simple C program :
#include<stdio.h>
main()
{
printf("Hello World");
}
-Then in cmd I wrote:
gcc helloworld.c -o helloworld.exe
And a dialog box pops out with the following error message :
Impossible to start program because libiconv.dll is missing on your computer. Reinstall program to correct problem.
The dll file does not appear in the lib folder of MinGW_w64. I tried to copy libiconv.a and libiconv.dll.a from the MinGW32 lib folder to the lib folder of MinGW_64, but still no luck.
Any ideas?
You need the DLL file, not the .a link library files. libiconv.dll should exist somewhere in the bin directory. If it is not there, you’ll need to get it from the internet or compile it yourself. Alternatively you could just link statically to the iconv library.
Once you find the DLL, make sure it is in one of the following locations:
* the %PATH%
* the appropriate C:\Windows\system32 or C:\Windows\SysWOW64 directory
* (preferably) next to your executable
I was able to fix the problem by downloading another version on the package on SourceForge.
Thanks!
I have installed a package libstree on my machine (x86_64/Redhat Linux).
Have followed the instructions ( ./configure --prefix=/usr; make check; make install) to install the package.
Have checked that the relevant header files are in the /usr/include and /usr/lib directories.
However when I try to compile a test program I get an error message:
test.c:6:25: fatal error: lst_structs.h: No such file or directory
compilation terminated.
lst_structs.h is present in the /usr/include/stree directory.
Anyone have any thoughts as to why the GNU C compiler cannot locate the header file?
As it's in an /include sub-directory, you need to explicitly mention it (see comments above), or adjust your lib include path, as outlined on this old stackoverflow post:
How to add a default include path for gcc in linux?
I'm enrolled in a masters computer science course. The course is using C and the instructor wants us to use Cygwin to compile programs if we are using windows.
I've downloaded and installed Cygwin and I've ensured that I've installed the GCC compiler.
But I don't know where to go from here. I need to compile a single source file that has a basic include.
#include <stdio.h>
Lets assume the file is on my desktop (it is not, but for the sake of argument). How do I navigate to the desktop from the bash shell? I assume once I've navigated to the correct location in bash, I simply execute:
gcc myProgram.c -o myProgram
Update: Following different instructions posted below, I was able to compile the program; I thank you for that. But when I execute the resulting binary I get the following. How can I compile or execute this program so I don't get the error? Again, thank you.
This application has failed to start because cygwin1.dll was not found. Re-installing the application may fix this problem.
when you start in cygwin, you are in your $HOME, like in unix generally, which maps to c:/cygwin/home/$YOURNAME by default. So you could put everything there.
You can also access the c: drive from cygwin through /cygdrive/c/ (e.g. /cygdrive/c/Documents anb Settings/yourname/Desktop).
Regarding your updated question about the missing cygwin1.dll.
From the Cygwin terminal check,
ls /usr/bin/cygwin1.dll
If it is not present (I doubt that), your installation is not properly done.
Then, check your path with,
echo $PATH
This will give : separated list of paths. It MUST contain /usr/bin. If you find that missing add it with,
export PATH=/usr/bin:$PATH
Finally,
I hope you are using Cygwin from the cygwin terminal (the little green+black icon installed with Cygwin), or MinTTY (if you installed that).
And, you have not moved the compiled EXE to a different machine which does not have Cygwin installed (if you do that, you will need to carry the cygwin1.dll to that machine -- keep it in the same folder as the compiled EXE).
Just to summarize, here are some commands that navigate to a directory and compile code using Cygwin and Windows Vista:
Start a Cygwin shell.
At the prompt, use cd to change to the appropriate directory:
$ cd /cygdrive/c/Users/nate/Desktop
Use ls to list the files in the directory:
$ ls
prog.c
Use the gcc command to compile a file in this directory:
$ gcc prog.c -o prog
If you don't see any errors, you should be able to run the resulting program:
$ ./prog
Update:
For the "Cygwin1.dll not found" error, I like Nik's answer. You might also check out this related post about cygwin1.dll not found, which suggests adding c:\cygwin\bin\ to your Windows PATH.
There are instructions on how to change the Windows PATH variable for Windows XP, and on Vista I think it's similar.
Go to Control Panel -> System
Select Advanced System Settings
Click on the Advanced tab
Click on Environment Variables
Under System Variables, find the Path entry and click Edit
Add c:\cygwin\bin to the list, making sure to separate it from any previous items with a semicolon
Look for (that is, cd to)
/cygdrive/c/
that will usually be your C:\
Also look at Using Cygwin, the Lifehacker introduction (June/2006) and, this biomed page at PhysioNet.
Regarding the cygwin1.dll not found error, a solution I have used for at least 8 years is to add the Cygwin bin directories to the end of my %PATH% in My Computer -> Properties -> Advanced -> Environment Variables. I add them to the end of the path so in my normal work, they are searched last, minimizing the possibility of conflicts (in fact, I have had no problems with conflicts in all this time).
When you invoke the Cygwin Bash Shell, those directories get prepended to the %PATH% so everything works as intended in that environment as well.
When not running in Cygwin shell, my %PATH% is:
Path=c:\opt\perl\bin; \
...
C:\opt\cygwin\bin; \
C:\opt\cygwin\usr\bin; \
C:\opt\cygwin\usr\local\bin;
This way, for example, ActiveState Perl's perl is found first when I am not in a Cygwin Shell, but the Cygwin perl is found when I am working in the Cygwin Shell.
If you are not comfortable with bash, you can continue to work in a standard windows command (i.e. DOS) shell.
For this to work you must add C:\cygwin\bin (or your local alternative) to the Windows PATH variable.
With this done, you may:
1) Open a command (DOS) shell
2) Change the directory to the location of your code (c:, then cd path\to\file)
3) gcc myProgram.c -o myProgram
As mentioned in nik's response, the "Using Cygwin" documentation is a great place to learn more.
If you just do gcc program.c -o program -mno-cygwin it will compile just fine and you won't need to add cygwin1.dll to your path and you can just go ahead and distribute your executable to a computer which doesn't have cygwin installed and it will still run. Hope this helps
Windows path C:\src under cygwin becomes /cygdrive/c/src
Compiling your C program using Cygwin
We will be using the gcc compiler on Cygwin to compile programs.
1) Launch Cygwin
2) Change to the directory you created for this class by typing
cd c:/windows/desktop
3) Compile the program by typing
gcc myProgram.c -o myProgram
the command gcc invokes the gcc compiler to compile your C program.
You might be better off editing a file inside of cygwin shell. Normally it has default user directory when you start it up. You can edit a file from the shell doing something like "vi somefile.c" or "emacs somefile.c". That's assuming vi or emacs are installed in cygwin.
If you want to file on your desktop, you'll have to go to a path similar (on XP) to "/cygwindrive/c/Documents\ and\ Settings/Frank/Desktop" (If memory serves correctly). Just cd to that path, and run your command on the file.
Cygwin is very cool! You can compile programs from other systems (Linux, for example), and they will work. I'm talking communications programs, or web servers, even.
Here is one trick. If you are looking at your file in the Windows File Explorer, you can type "cd " in your bash windows, then drag from explorer's address bar into the cygwin window, and the full path will be copied! This works in the Windows command shell as well, by the way.
Also: While "cd /cygdrive/c" is the formal path, it will also accept "cd c:" as a shortcut. You may need to do this before you drag in the rest of the path.
The stdio.h file should be found automatically, as it would be on a conventional system.
This file (cygwin1.dll) is cygwin dependency similar to qt dependency.you must copy this file and similar files that appear in such messages error, from "cygwin/bin" to folder of the your program .Also this is necessary to run in another computer that have NOT cygwin!