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Linking .a library file

Dear sir,

I am trying to use the NIST Fingerprint Qaulity library in my c code i have written code like,

Code:

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <strings.h>



#include <nfiq/imgtype.h>

#include <nfiq/imgdecod.h>

#include <nfiq/nfiq.h>

#include <nfiq/mlp.h>





typedef struct opt_flags_s {

  int verbose;

  int old_mode;

  int has_attribs;

} OPT_FLAGS;





int main (void)

{



int quality;



// system("./nfiq -v /home/Desktop/2nd.jpg");



  

  int ret;

  char *imgfile = "/home/Desktop/2nd.jpg";

  unsigned char *idata;

  int img_type, ilen, iw, ih, id, ippi;

  int nfiq;

  float conf;

  OPT_FLAGS flags = { 0, 0, 0 };



        /* This routine will automatically detect and load:        */

        /* ANSI/NIST, WSQ, JPEGB, JPEGL, and IHead image formats  */

        if((ret = read_and_decode_grayscale_image(imgfile, &img_type,

                    &idata, &ilen, &iw, &ih, &id, &ippi))) {

            if(ret == -3) /* UNKNOWN_IMG */

              fprintf(stderr, "Hint: Use -raw for raw images\n");

            exit(ret);

        }



      /* Compute the NFIQ value */

      ret = comp_nfiq(&nfiq, &conf, idata, iw, ih, id, ippi, &flags.verbose);

      /* If system error ... */

      if(ret < 0) {

        free(idata);

        exit(ret);

      }



      /* Report results to stdout */

//      if (flags.verbose == 0) {

            printf("%d\n", nfiq);

//      } else if(flags.verbose == 1) {

            printf("%d\t%4.2f\n", nfiq, conf);

//      }



      /* Deallocate image data */

      free(idata);



}

i wanted to link the two libraries libnifq and lib image
i have tried like this in my Makefile

Code:

g++ -o quality quality.c -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

and i am getting error

Code:

:~/quality_separate$ make

g++ -o quality    quality.c    -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

quality.c: In function ‘int main()’:

quality.c:40:20: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings]

/tmp/ccBkn9nJ.o: In function `main':

quality.c:(.text+0x6c): undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)'

quality.c:(.text+0xf8): undefined reference to `comp_nfiq(int*, float*, unsigned char*, int, int, int, int, int*)'

collect2: ld returned 1 exit status

make: *** [all] Error 1

The API's showing undefined reference in error are present in the above included header files imgtype.h, imgdecod.h, nfiq.h, mlp.h

where i am making mistake please let me know and help me to solve the issue

Thanks & Regards
rohaan

Header files are typically used for declaring functions, however, and again typically, the implementation for such functions is done within the library file.

You indicated that you are using a static library 'libnfiq.a' and 'libimage.a'. You should check each of these to ensure that the unreferenced functions are indeed present. For example:

Code:

$ nm libnfiq.a | grep comp_nfiq



$ nm libimage.a | grep read_and_decode_grayscale_image

you have missed some -I <path/to/include/files> flags

Quote:

Originally Posted by dwhitney67 (Post 5026516)

Code:

$ nm libnfiq.a | grep comp_nfiq



$ nm libimage.a | grep read_and_decode_grayscale_image

Dear sir thanks for reply
i tried your suggested things i thing the libraries got the function i am trying to use as the out of above commands are

Code:

ivb@ivb-desktop:~/quality_separate$ nm libnfiq.a | grep comp_nfiq

000006c0 T comp_nfiq

00000000 T comp_nfiq_featvctr

00000350 T comp_nfiq_flex

ivb@ivb-desktop:~/quality_separate$ nm libimage.a | grep read_and_decode_grayscale_image

00000d80 T read_and_decode_grayscale_image

ivb@ivb-desktop:~/quality_separate$

Regards
Rohaan

Quote:

Originally Posted by pan64 (Post 5026523)

you have missed some -I <path/to/include/files> flags

Dear sir,

Can you please let me know briefly so that i can learn from this mistake where i am going wrong

my library are present at the /home/ivb/quality_separate so i used -L symbol to get to the directory and then used the -l to link respective library. and header files are included in C code Itself. If possble Can you please help regarding this

Code:

-L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

Thanking you,
rohaan

to compile something.c you need header files, you specify the location of headers by -I <path>. you will specify the name of the required headers in the source files by #include <filename> lines.
lo link several object files into an app you may need libraries, and you need to specify the location of those libs by -L <path>. you will specify the name of the required libs by -l <name-of-the-lib>

Code:

# so step one:

g++ -o quality.o -c quality.c -I <path1> -I<path2> ....

# this will create quality.o

# step two:

g++ -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

# this will create the app quality.



# all the above in one step:

g++ -o quality quality.c -I <path1> -I<path2>  -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

you have some #includes in your source but the corresponding -I <path> is missing
(you need not use -I, -L and -l for default headers and libs)

Quote:

Originally Posted by pan64 (Post 5026904)

Code:

# so step one:

g++ -o quality.o -c quality.c -I <path1> -I<path2> ....

# this will create quality.o

# step two:

g++ -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

# this will create the app quality.



# all the above in one step:

g++ -o quality quality.c -I <path1> -I<path2>  -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

you have some #includes in your source but the corresponding -I <path> is missing
(you need not use -I, -L and -l for default headers and libs)

Dear sir,
Thanks for such clean reply i got your point. i think we might need to give the path of the Header files -I<Path> when we are not using the defualt header files
i tried your suggestions so my make file look like

Code:

all:

        # so step one:

        g++ -o quality.o -c quality.c -I /usr/include/nfiq  -I usr/include/nfiq

        

        # this will create quality.o

        # step two:

        g++ -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq  -L /home/ivb/quality_separate -l image

        # this will create the app quality.



#      all the above in one step:

#      g++ -o quality quality.c  -I /usr/include/nfiq/  -I /usr/include/nfiq/  -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image



clean:

        rm -f quality.o quality 

help:

        @echo  'make          would compile and create the library and create a link'

        @echo  'make clean    would remove the object file and executables'

but i am still getting the same results

Code:

$ make

# step one:

g++ -o quality.o -c quality.c -I /usr/include/nfiq  -I /usr/include/nfiq

quality.c: In function ‘int main()’:

quality.c:40:20: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings]

# this will create quality.o

# step two:

g++ -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq  -L /home/ivb/quality_separate -l image

quality.o: In function `main':

quality.c:(.text+0x6c): undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)'

quality.c:(.text+0xf8): undefined reference to `comp_nfiq(int*, float*, unsigned char*, int, int, int, int, int*)'

collect2: ld returned 1 exit status

make: *** [all] Error 1

Regards
rohaan

so first step works, you have got an error during the second step. It means you have a missing lib from that command.
do you have both libimage.so and libimage.a? Do you haev both libnfiq.so and libnfiq.a?

Quote:

Originally Posted by pan64 (Post 5026943)

No sir i just have libimage.a and libnfiq.a

Regards
rohaan

please compile with g++ -g .... (so add -g to both lines) and post the result.
also can you try gcc intead of g++ (that means gcc -o .....)
thanks

Quote:

Originally Posted by pan64 (Post 5026949)

please compile with g++ -g .... (so add -g to both lines) and post the result.
also can you try gcc intead of g++ (that means gcc -o .....)
thanks

Sir if i use gcc instead of g++ it gives undefined reference to everything I think it doesnt link the library
results

Code:

$ make

# so step one:

gcc  -o quality.o -c quality.c -I /usr/include/nfiq  -I /usr/include/nfiq

# this will create quality.o

# step two:

gcc  -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq  -L /home/ivb/quality_separate -l image

/home/ivb/quality_separate/libnfiq.a(nfiq.o): In function `comp_nfiq_flex':

nfiq.c:(.text+0x3a4): undefined reference to `lfsparms_V2'

nfiq.c:(.text+0x460): undefined reference to `get_minutiae'

nfiq.c:(.text+0x4d4): undefined reference to `free_minutiae'

nfiq.c:(.text+0x5a0): undefined reference to `free_minutiae'

nfiq.c:(.text+0x644): undefined reference to `runmlp2'

nfiq.c:(.text+0x687): undefined reference to `free_minutiae'

/home/ivb/quality_separate/libnfiq.a(znorm.o): In function `comp_znorm_stats':

znorm.c:(.text+0x116): undefined reference to `ssx_stddev'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `ihead_decode_mem':

imgdecod.c:(.text+0x2c): undefined reference to `get_width'

imgdecod.c:(.text+0x38): undefined reference to `get_height'

imgdecod.c:(.text+0x44): undefined reference to `get_depth'

imgdecod.c:(.text+0x50): undefined reference to `get_density'

imgdecod.c:(.text+0x5c): undefined reference to `get_compression'

imgdecod.c:(.text+0x118): undefined reference to `get_complen'

imgdecod.c:(.text+0x1bc): undefined reference to `set_compression'

imgdecod.c:(.text+0x1cc): undefined reference to `set_complen'

imgdecod.c:(.text+0x220): undefined reference to `inv_bytes'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `.L26':

imgdecod.c:(.text+0x3a0): undefined reference to `png_decode_mem'

imgdecod.c:(.text+0x3e4): undefined reference to `get_IMG_DAT_image'

imgdecod.c:(.text+0x412): undefined reference to `free_IMG_DAT'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `.L25':

imgdecod.c:(.text+0x4d0): undefined reference to `openjpeg2k_decode_mem'

imgdecod.c:(.text+0x514): undefined reference to `get_IMG_DAT_image'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `.L23':

imgdecod.c:(.text+0x660): undefined reference to `jpegb_decode_mem'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `.L21':

imgdecod.c:(.text+0x708): undefined reference to `wsq_decode_mem'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `.L22':

imgdecod.c:(.text+0x7e0): undefined reference to `jpegl_decode_mem'

imgdecod.c:(.text+0x824): undefined reference to `get_IMG_DAT_image'

imgdecod.c:(.text+0x928): undefined reference to `free_IMG_DAT'

/home/ivb/quality_separate/libimage.a(imgdecod.o): In function `read_and_decode_grayscale_image':

imgdecod.c:(.text+0xdd2): undefined reference to `is_ANSI_NIST_file'

imgdecod.c:(.text+0xf27): undefined reference to `read_ANSI_NIST_file'

imgdecod.c:(.text+0xf97): undefined reference to `get_first_grayprint'

imgdecod.c:(.text+0xfb5): undefined reference to `free_ANSI_NIST'

imgdecod.c:(.text+0x1092): undefined reference to `free_ANSI_NIST'

imgdecod.c:(.text+0x10ec): undefined reference to `free_ANSI_NIST'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `.L2':

imgutil.c:(.text+0x34): undefined reference to `fatalerr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `SizeFromDepth':

imgutil.c:(.text+0x109): undefined reference to `ceil'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `init_image_data':

imgutil.c:(.text+0x1f6): undefined reference to `syserr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `WordAlignFromDepth':

imgutil.c:(.text+0x231): undefined reference to `ceil'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `allocate_image':

imgutil.c:(.text+0x320): undefined reference to `calloc_uchar'

imgutil.c:(.text+0x3aa): undefined reference to `fatalerr'

imgutil.c:(.text+0x402): undefined reference to `fatalerr'

imgutil.c:(.text+0x45a): undefined reference to `fatalerr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `mallocate_image':

imgutil.c:(.text+0x500): undefined reference to `malloc_uchar'

imgutil.c:(.text+0x58a): undefined reference to `fatalerr'

imgutil.c:(.text+0x5e2): undefined reference to `fatalerr'

imgutil.c:(.text+0x63a): undefined reference to `fatalerr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `alloc_short_image':

imgutil.c:(.text+0x6ba): undefined reference to `syserr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `alloc_char_image':

imgutil.c:(.text+0x73a): undefined reference to `syserr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `alloc_int_image':

imgutil.c:(.text+0x7aa): undefined reference to `syserr'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `width_16':

imgutil.c:(.text+0x7e9): undefined reference to `ceil'

/home/ivb/quality_separate/libimage.a(imgutil.o): In function `allocate_aligned_image':

imgutil.c:(.text+0x94e): undefined reference to `fatalerr'

imgutil.c:(.text+0x976): undefined reference to `fatalerr'

imgutil.c:(.text+0x9a6): undefined reference to `fatalerr'

imgutil.c:(.text+0x9d2): undefined reference to `syserr'

/home/ivb/quality_separate/libimage.a(imgtype.o): In function `jpeg_type':

imgtype.c:(.text+0x46): undefined reference to `getc_marker_jpegl'

imgtype.c:(.text+0x80): undefined reference to `getc_marker_jpegl'

imgtype.c:(.text+0xb8): undefined reference to `getc_skip_marker_segment'

imgtype.c:(.text+0xd8): undefined reference to `getc_marker_jpegl'

/home/ivb/quality_separate/libimage.a(imgtype.o): In function `image_type':

imgtype.c:(.text+0x220): undefined reference to `getc_ushort'

imgtype.c:(.text+0x32d): undefined reference to `png_sig_cmp'

imgtype.c:(.text+0x38c): undefined reference to `is_ANSI_NIST'

/home/ivb/quality_separate/libimage.a(intrlv.o): In function `compute_component_padding':

intrlv.c:(.text+0xaf): undefined reference to `ceil'

intrlv.c:(.text+0xfa): undefined reference to `ceil'

intrlv.c:(.text+0x147): undefined reference to `ceil'

intrlv.c:(.text+0x195): undefined reference to `ceil'

/home/ivb/quality_separate/libimage.a(intrlv.o): In function `intrlv2not_mem':

intrlv.c:(.text+0x2c2): undefined reference to `ceil'

/home/ivb/quality_separate/libimage.a(intrlv.o):intrlv.c:(.text+0x31f): more undefined references to `ceil' follow

/home/ivb/quality_separate/libimage.a(imageops.o): In function `WordAlignImage':

imageops.c:(.text+0xa3): undefined reference to `malloc_uchar'

/home/ivb/quality_separate/libimage.a(img_io.o): In function `read_raw_from_filesize':

img_io.c:(.text+0x26): undefined reference to `filesize'

/home/ivb/quality_separate/libimage.a(img_io.o): In function `write_raw_or_ihead':

img_io.c:(.text+0x791): undefined reference to `nullihdr'

img_io.c:(.text+0x7a1): undefined reference to `set_id'

img_io.c:(.text+0x7a9): undefined reference to `set_created'

img_io.c:(.text+0x7b9): undefined reference to `set_width'

img_io.c:(.text+0x7c9): undefined reference to `set_height'

img_io.c:(.text+0x7d5): undefined reference to `set_depth'

img_io.c:(.text+0x7e5): undefined reference to `set_density'

img_io.c:(.text+0x7f5): undefined reference to `set_align'

img_io.c:(.text+0x805): undefined reference to `set_compression'

img_io.c:(.text+0x815): undefined reference to `set_complen'

img_io.c:(.text+0x82a): undefined reference to `set_whitepix'

img_io.c:(.text+0x836): undefined reference to `writeihdr'

img_io.c:(.text+0x89c): undefined reference to `set_whitepix'

/home/ivb/quality_separate/libimage.a(readihdr.o): In function `ReadBinaryRaster':

readihdr.c:(.text+0x3a): undefined reference to `readihdr'

readihdr.c:(.text+0x4a): undefined reference to `get_depth'

readihdr.c:(.text+0x73): undefined reference to `fatalerr'

readihdr.c:(.text+0x7b): undefined reference to `get_width'

readihdr.c:(.text+0x86): undefined reference to `get_height'

readihdr.c:(.text+0x94): undefined reference to `get_density'

readihdr.c:(.text+0xa2): undefined reference to `get_compression'

readihdr.c:(.text+0xae): undefined reference to `get_complen'

readihdr.c:(.text+0xf1): undefined reference to `malloc_uchar'

readihdr.c:(.text+0x162): undefined reference to `malloc_uchar'

readihdr.c:(.text+0x1fc): undefined reference to `fatalerr'

readihdr.c:(.text+0x240): undefined reference to `set_compression'

readihdr.c:(.text+0x250): undefined reference to `set_complen'

readihdr.c:(.text+0x2cc): undefined reference to `syserr'

readihdr.c:(.text+0x2e8): undefined reference to `inv_bytes'

/home/ivb/quality_separate/libimage.a(readihdr.o): In function `ReadIheadRaster':

readihdr.c:(.text+0x390): undefined reference to `readihdr'

readihdr.c:(.text+0x3d0): undefined reference to `fatalerr'

readihdr.c:(.text+0x411): undefined reference to `fatalerr'

readihdr.c:(.text+0x44f): undefined reference to `fatalerr'

readihdr.c:(.text+0x490): undefined reference to `fatalerr'

readihdr.c:(.text+0x4d0): undefined reference to `fatalerr'

readihdr.c:(.text+0x51a): undefined reference to `malloc_uchar'

readihdr.c:(.text+0x58a): undefined reference to `fatalerr'

readihdr.c:(.text+0x5da): undefined reference to `malloc_uchar'

readihdr.c:(.text+0x78c): undefined reference to `syserr'

readihdr.c:(.text+0x7a8): undefined reference to `inv_bytes'

collect2: ld returned 1 exit status

make: *** [all] Error 1

and with g++ -g option i get same result

Code:

# step one:

g++ -g -o quality.o -c quality.c -I /usr/include/nfiq  -I /usr/include/nfiq

quality.c: In function ‘int main()’:

quality.c:40:20: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings]

# this will create quality.o

# step two:

g++ -g -o  quality    quality.o    -L /home/ivb/quality_separate -l nfiq  -L /home/ivb/quality_separate -l image

quality.o: In function `main':

/home/ivb/quality_separate/quality.c:55: undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)'

/home/ivb/quality_separate/quality.c:64: undefined reference to `comp_nfiq(int*, float*, unsigned char*, int, int, int, int, int*)'

collect2: ld returned 1 exit status

make: *** [all] Error 1

Regards
rohaan

-g is used to keep debug info. You can see the differences - without -g:
quality.c:(.text+0x6c): undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)
with -g:
/home/ivb/quality_separate/quality.c:55: undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)'

So the first step is ok again, in the second step you got another errors, the previous errors were not displayed. I think you need to add more libs with -l. What kind of libs do you have next to libimage?
(please try to use gcc -g ...)

Quote:

Originally Posted by pan64 (Post 5026956)

Dear sir,

Ok i will there some more lib i dont think these are relevent but i will try and link and compile as i want to use it as app

one technical doubt,

i am doing this to add two lib

Code:

g++ -o quality quality.o -L /home/ivb/quality_separate -l nfiq -L /home/ivb/quality_separate -l image

for adding multiple lib do i nedd to give the directory location each and every time for same directory or

Code:

g++ -o quality quality.o -L /home/ivb/quality_separate -l nfiq -l image -l lib3 -lib4

will do??

-L /home/ivb/quality_separate (or any other dir) should be specified only once.

Quote:

Originally Posted by pan64 (Post 5026971)

-L /home/ivb/quality_separate (or any other dir) should be specified only once.

Dear sir,

This time i linked all the lib i have from the NIST site for running the quality code
i did through terminal and got simillar result like,

Code:

$ gcc -o quality quality.o -L /home/ivb/quality_separate/ -l nfiq -l image -l cblas -l fet -l jpegl -l pca -l png -l z -l clapck -l fft -l ioutil -l mindtct -l nfseg -l pcautil -l util -l bozorth3 -l f2c -l ihead -l jpegb -l mlp -l openjpeg -l pcax -l wsq

quality.o: In function `main':

quality.c:(.text+0x6c): undefined reference to `read_and_decode_grayscale_image(char*, int*, unsigned char**, int*, int*, int*, int*, int*)'

quality.c:(.text+0xf8): undefined reference to `comp_nfiq(int*, float*, unsigned char*, int, int, int, int, int*)'

collect2: ld returned 1 exit status

Regards
rohaan