Do the names of the args passed to main() matter

Question

I know that to use command line arguments in C you do something like this:

int main(int argc, char **argv)
{
//use argc and argv
}

Today I was thinking about it and I realized I have never not seen them called argc and argv. Is it a requirement that they are called this or is it just convention? If it is required why is this the case?

Could I do something like this:

int main(int length, char**myinput){
//use length as you would argc and myinput
// as you would argv
}

I haven't had a chance to write a program to test it out yet.

`argc` and `args` is just a convention that came down from the time where characters were precious... — cmaster - reinstate monica, Nov 11 '14 at 20:53
You should *totally* call them like: `int main(int NumberOfProgramArguments, char **NullTerminatedArrayOfPointersToProgramArguments )` — 2501, Nov 11 '14 at 20:54
@LyingOnTheSky that's seldom true for C. Lots of things can appear to work when in fact they don't. — Quentin, Nov 11 '14 at 20:54
@2501 However, any decent C programmer will recognize the meaning of `int main(int argc, char** args)`... — cmaster - reinstate monica, Nov 11 '14 at 20:55
@2501 I don't have any problem using `argv` and `argc` I was just curious — user3282276, Nov 11 '14 at 20:55
@Quentin What do you mean? If you test it out and it works, there's a chance that it's imaginary not really works? I don't get it I think. — LyingOnTheSky, Nov 11 '14 at 20:59
This may explain the etymology of argc and argv: [Where did the convention of naming command line arguments as 'argv' come from?](https://programmers.stackexchange.com/questions/196654/where-did-the-convention-of-naming-command-line-arguments-as-argv-come-from) — , Nov 11 '14 at 21:08
@LyingOnTheSky I insist on "*appear* to work". Undefined behaviour is one such source of things that seem to work until they don't work anymore for no apparent reason. — Quentin, Nov 11 '14 at 23:02
@Quentin If it's undefined behaviour, then it's different, but if none said it. You actually found an interesting question, why in this specific situation, that behaviour is occurring. — LyingOnTheSky, Nov 12 '14 at 09:03
@LyingOnTheSky no one mentionned it indeed, but it's just a fair warning that in C you can't just "try it and see if it works", because invisible bugs do exist :) — Quentin, Nov 12 '14 at 09:18

score 5 · Accepted Answer · edited May 23 '17 at 11:58

The C standard says that you can call them whatever you want.

5.1.2.2.1 Program startup

1 The function called at program startup is named main. The implementation declares no prototype for this function. It shall be defined with a return type of int and with no parameters:
int main(void) { /* ... */ }
or with two parameters (referred to here as argc and argv, though any names may be used, as they are local to the function in which they are declared): [..]

In What does int argc, char *argv[] mean?, answerer meager says that argc and argv are named so by convention (argument count and argument vector respectively).

score 2 · Answer 2 · answered Nov 11 '14 at 20:53

2

It is just a convention, there is no requirement on the names. They are user-defined parameters like any other, so use whatever names you want.

answered Nov 11 '14 at 20:53

Remy Lebeau

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Do the names of the args passed to main() matter

2 Answers2