Question

I have searched the site and I haven’t found an answer to my problem.

My program outputs an image, and I want to save to a different file, each image produced after an cycle iteration.

My code to save files is this

FILE *fobjecto;
if ((fobjecto = fopen ("OSEM.ima", "wb")) != NULL)                 
{   
    printf("Writing reconstructed image file"); 
    fwrite (objecto, sizeof(float), (detectorXDim)*detectorYDim*(NSlices-1), fobjecto);    
    fclose (fobjecto);     
}    
else    
    printf("Reconstructed image file could not be saved");

I want to add one integer variable to the output file’s name, I have tried playing with “+” and “,” but I could not solve it.

Thanks in advance

Answer 1

You will need some formatted output operation like sprintf (or even better its safe twin snprintf):

char buf[512]; // something big enough to hold the filename
unsigned int counter;
FILE * fobjecto;

for (counter = 0; ; ++counter)
{
  snprintf(buf, 512, "OSEM_%04u.ima", counter);

  if ((fobjecto = fopen(buf, "wb")) != NULL) { /* ... etc. ... */ }

  // Filenames are OSEM_0000.ima, OSEM_0001.ima, etc.
}