failed to build example.c code(following the C-API) using static library(libfreesasa.a)

mittinatten / freesasa

C-library for calculating Solvent Accessible Surface Areas

MIT License

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Hi, I tried to build the example.c code following the C-API as demonstrated in http://freesasa.github.io/doxygen/API.html. Unfortunately, it does not work. More specifically, I first tried to build and make install the source code using the following command

git submodule init
git submodule update
autoreconf -i 
./configure --prefix=my_install_location --disable-json
make && make install

It successfully built the shared library with the following files:

/my_install_location/include/freesasa.h
/my_install_location/bin/freesasa
/my_install_location/lib/libfreesasa.a
/my_install_location/share/some_other_files

I tested the executable my_install_location/bin/freesasa, and it works well.

Then I wrote an example.c code following the C-API:

#include <stdio.h>
#include "freesasa.h"

void main()
{
    FILE *fp = fopen("1ubq.pdb", "r");
    const freesasa_classifier *classifier = &freesasa_default_classifier;
    freesasa_structure *structure = freesasa_structure_from_pdb(fp, classifier, 0);

    freesasa_result *result = freesasa_calc_structure(structure, NULL);
    printf("Total area: %f A2\n",result->total);
}

and built it using the following command:

gcc -I/my_install_location/include -L/my_install_location/lib -lfreesasa -static example.c -o example

It raised the following error message:

/tmp/cc2tQGTg.o: In function `main':
example.c:(.text+0x22): undefined reference to `freesasa_protor_classifier'
example.c:(.text+0x3e): undefined reference to `freesasa_structure_from_pdb'
example.c:(.text+0x53): undefined reference to `freesasa_calc_structure'
collect2: error: ld returned 1 exit status
Makefile:2: recipe for target 'target' failed
make: *** [target] Error 1

It seems gcc has successfully load the .h and .a file into the system, but it did not find a reference of freesasa_protor_classifier, freesasa_structure_from_pdb, freesasa_calc_structure as defined in the header file. (As you can see, freesasa_protor_classifier does not appear in the example.c file)

I'm a new comer of c-language, so maybe I made a mistake during the building process. Could you provide me some hint on what's going on and how could I fix this?

Thanks a lot in advance

include "freesasa.h"

void main() { FILE fp = fopen("1ubq.pdb", "r"); const freesasa_classifier classifier = &freesasa_default_classifier; freesasa_structure *structure = freesasa_structure_from_pdb(fp, classifier, 0);

freesasa_result *result = freesasa_calc_structure(structure, NULL); printf("Total area: %f A2\n",result->total);

}

and built it using the following command:

gcc -I/my_install_location/include -L/my_install_location/lib -lfreesasa -static example.c -o example

It raised the following error message:

/tmp/cc2tQGTg.o: In function main': example.c:(.text+0x22): undefined reference tofreesasa_protor_classifier' example.c:(.text+0x3e): undefined reference to freesasa_structure_from_pdb' example.c:(.text+0x53): undefined reference tofreesasa_calc_structure' collect2: error: ld returned 1 exit status Makefile:2: recipe for target 'target' failed make: *** [target] Error 1

It seems gcc has successfully load the .h and .a file into the system, but it did not find a reference of freesasa_protor_classifier, freesasa_structure_from_pdb, freesasa_calc_structure as defined in the header file. (As you can see, freesasa_protor_classifier does not appear in the example.c file)

I'm a new comer of c-language, so maybe I made a mistake during the building process. Could you provide me some hint on what's going on and how could I fix this?

Thanks a lot in advance

mittinatten / freesasa

failed to build example.c code(following the C-API) using static library(libfreesasa.a) #90

include

include "freesasa.h"