sprintf giving me issues

**sl4nted** · 11-14-2006

Code:

temp = malloc(strlen(modelname) + strlen(inc) + strlen("Lightcurves\\") + 1);
sprintf(temp, "%s%s%s%s", "Lightcurves\\", modelname, inc, ".mag");

your allocating enough room for modelname, inc, Lightcurves\\ and '/0'

then putting Lightcurves\\, modelname, inc and ".mag" in it.

there needs to be room for ".mag"......but really since it looks like the size of temp is the same each
iteration of the loop, you should just declare it statically, instead of allocating and freeing each time each time.

p.s. don't forget to close out somewhere

**vart** · 11-14-2006

It is not enough
"Lightcurves\\modelB.00.mag"
takes more than 20 characters allocated in the modelfile array, so each strcpy(modelfile[i/5], temp); overwrites some additional bytes...

**sl4nted** · 11-14-2006

Code:

#include <stdio.h>

char modelname[] = "modelname.";

void fitCurves()
{
     int i;
     char inc[3];
     char modelfile[18][30];


     out = fopen("bestinc.txt", "a+"); //Opens file to write results to.
     fprintf(out, "i\tX^2\n"); //Prints header in periods.txt.
     fclose(out);

     for (i = 0; i < 18; i++) {

         sprintf(inc, "%02d", i*5);
         sprintf(modelfile[i], "Lightcurves\\%s%s.mag", modelname, inc);

         printf("%s\n", modelfile[i]);

         model = openFile(modelfile[i]);
         fclose(model);

     }
}

int main(void)
{
        fitCurves();
        return 0;
}

I'm not sure if model is global or what. but this should fix some stuff

**vart** · 11-14-2006

Code:

         sprintf(inc, "%02d", i*5);
         sprintf(modelfile[i], "Lightcurves\\%s%s.mag", modelname, inc);

is equivalent to

Code:

         sprintf(modelfile[i], "Lightcurves\\%s%02d.mag", modelname, i*5);

Code:

char modelname[] = "modelname.";

can be replaced by

Code:

const char *modelname = "modelname.";

out should be checked before use

Code:

void fitCurves()

better declare as

Code:

void fitCurves(void)

**sl4nted** · 11-14-2006

and also using wierd numbers like char modelname[18][30] should be replaced with
something like

Code:

#define NFILES 18         /*number of files of type modelname */
#define NAMELEN 30   /* maximum length of the filename */
....
....
in function
...
char modelname[NFILES][NAMLEN]
...
...
for (i= 0; i < NFILES; i++)

makes it easier to see whats happening as well as easier to change it if need be.

Code:

sprintf(modelfile[i], "Lightcurves\\%s%s.mag", modelname, inc);

may have to be

Code:

sprintf(modelfile[i], "Lightcurves\\\\%s%s.mag", modelname, inc);

but really if your not using inc for anything else, you should just do what vart suggested
and combine it to one sprintf, and get rid of inc all together

**dwks** · 11-14-2006

Declare it without the asterisk as mentioned.

Code:

char *modelfile[19][20];

->

Code:

char modelfile[19][20];

Then make sure openFile() takes a char* or char[] or char[20] as its argument.

Also add 4 to the amount of memory that you allocate, for ".mag".

[edit] Woah, way too slow . . . [/edit]

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