Question

I’m trying to do something like

strcmp(argv[3], "stdout")

however, in the command line I don’t want to type

stdout\0

what’s the best way to get rid of the \0 at the end of a string literal?

Thanks!

update:

Thanks guys. I found what’s wrong with my code… I should have used

strcmp(argv[3], "stdout") == 0

Thanks @Nicol Bolas

Answer 1

You don’t have to type “stdout\0” on the command line. Whichever way your system makes command-line arguments available to your process (it differs by operating system) automatically adds the null character.

As you know, a C-style string is terminated by the null character, which is written in code as ‘\0’. If that character weren’t at the end of the string, a function such as strcmp would keep going well beyond the end of the string, since such a string flouts convention. Since the terminating null character is the C convention, however, the compiler is smart enough to add the null character to the end of a string literal, and the system is smart enough to add the null character to the command-line arguments stored in the memory of a freshly created process. If argc is greater than 3, and the third argument you type on the command-line for your program is “stdout”, the call to strcmp(argv[3], "stdout") will return 0 to mean that the two strings match.