Strings Based on Variables

Question

Say I have variables double x, y, z; and I want to make a txt file with a name based on those variables e.g. "GenericName_x_y_z.txt".

How would I create the string?

I know functions like printf("GenericName_%.2f_%.2f_%.2f.txt", x, y, z) you can do, but how would I define a string like that, not just print it?

So then I can use

char filename[] = "GenericName_%.2f_%.2f_%.2f.txt";

FILE* fPointer;
fPointer = fopen(filename, "w");

I'm sorry the phrasing is really terrible and its probably a really basic thing I'm not getting!

Thanks

Your title is somewhat misleading. You're not looking for filenames based on variables but for strings basd on variables. — Jabberwocky
– Jabberwocky, Commented Apr 14, 2020 at 15:08

Jonathan Leffler · Accepted Answer · 2020-04-14 15:07:55Z

3

You're looking for snprintf():

char filename[128];
snprintf(filename, sizeof(filename), "GenericName_%.2f_%.2f_%.2f.txt", x, y, z);

answered Apr 14, 2020 at 15:07

Jonathan Leffler

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