Hi Chris, In the getting started section of the second project sheet, mkdir is listed as a system call that we may use. In the project requirements and fine print section of the project sheet point 8 reads: Your project must not invoke the standard utility programs cp or mkdir, or call the library function system(). Are we or are we not to use the mkdir system call? Thank you

ANONYMOUS wrote: There is a program (utility program) named mkdir, which you may not use. But there's also a system-call named mkdir() which you may use. The exact same is true for chmod and getopt .

Thanks for pointing this out, I was just about to ask about this. As mkdir is a utility program that is called in the command line, how is it possible to use it in the C program? Could you highlight an exmaple of each in case I end up doing something stupid in my program?

"Lewei Xu" <23*0*0*8@s*u*e*t*u*a*e*u*a*> wrote: We can trivially call a command-line utility from within a C program by using for() and execl(). But the mkdir program does little more than call the mkdir() system-call, which we can do from within our own program. If the action performed by an external program was far more significant, such as sort or zip, then it'd make far more sense to spawn the external program.