Thread: concatenation of strings and integers then call into a function

I have a very simple question. I would like to concatenate strings so that

Code:

char *string0 = "/home/myComputer/someFolder/fileName_";
char ext[4] = ".raw";
char fname[256];

int someNumber;

sprinrf(fname, "%s%d%s", string0, someNumber, ext); // my problem is here

int begin = 0;
int end = 10;

someFunction(fname, begin, end);

What i want to do is if I call someFunction (....), I want someNumber to be free so that i can use the variables begin and end to replace it , so that
someFunction("/home/myComputer/someFolder/fileName_%d.raw", begin, end);


Thanks!

And what exactly is the problem?

You may want to assign a value to your number before you try to use it. And your ext[] doesn't have enough room for the required end of string character. You need at least a size of 5.

Jim

Thanks Jim.
Thanks for pointing out the mistake in ext[].

someFunction is part of a bigger for-loop so that when someFunction is called, it will do some more complicated for-loops. The idea is, I want define a larger string first by concatenation of a string, an integer and another string. However the integer will only be supplied only when the string is used in someFunction(....)

There might be a better way to address this???

The idea is, I want define a larger string first by concatenation of a string, an integer and another string. However the integer will only be supplied only when the string is used in someFunction(....)

Then you need to wait to concatenate the strings until you know the number.

Jim

Originally Posted by fclopez

What i want to do is if I call someFunction (....), I want someNumber to be free so that i can use the variables begin and end to replace it , so that
someFunction("/home/myComputer/someFolder/fileName_%d.raw", begin, end);

You have to first create the format string by concatenating all the parts (including the %d format specifier) and then later use this format string:

Code:

#include <stdio.h>

int main(void)
{
    char *string0 = "/home/myComputer/someFolder/fileName_";
    char ext[4] = ".raw";
    char fname[256];
     
    puts("Create format string for later processing:");
    sprintf(fname, "%s%s%s", string0, "%d", ext); 
    puts(fname);
     
    int begin = 0, end = 10, i;
    
    puts("\nNow insert number into created format string:");
    for (i = begin; i < end; i++)
    {
        printf(fname, i);
        putchar('\n');
    }
        
    return 0;
}

Is that what you want?

Bye, Andreas