how to pass int/char into system() a Linux system call

Question

Ok it might sounds dumb, but I couldn't figure out a way to pass int/char into this system call

here is how I would like it to work

system ("cal %d %d", month, year);

I expect this will give me the following command on terminal "cal 3 2009"

and the terminal will show me the calendar of March 2009.

But the compiler is complaining it has too many arguments

any ideas? I need to make this method system ("cal ") return me a dynamic calendar.

Notes: cal take the argument cal month year

Answer 1

You need to build the proper command line string, system() won't do it for you:

char cmd[64];

snprintf(cmd, sizeof cmd, "cal %d %d", month, year);
system(cmd);

The usual caveats about buffer overflow apply, although in this particular case when both arguments are integers you should be fairly safe.