Explanation of a function

[DrJones]

Hi, can someone tell me, in extended terms what this function parameters are

what does char* buf, const .... etc mean


int sprintf ( char *buf, const char *format, ... );
int snprintf( char *buf, size_t n, const char *format, ... );


like printf has its format... (string ,then variable)

whats sprintfs format.

Thanks

Greg

[Prelude]

printf:

printf ( "%d\n", 10 );

sprintf:

char buf[4];

sprintf ( buf, "%d\n", 10 );

snprintf:

char buf[4];

snprintf ( buf, 4, "%d\n", 10 );

-Prelude

[MortalMonkey]

I've found good use for sizeof() in such functions as snprintf. You never know when you're going to resize the buffer a little, and when you do, it can be a real pain to dig up all those hardcoded size limiters.

char buf[4];

snprintf ( buf, sizeof(buf), "%d\n", 10 );

[vsriharsha]

I've seen many functions (or maybe its an un-official convention) when ever you see an 'n' in a function name, you can guess that the function involves a parameter for 'Number of Items/characters/etc'.

sprintf() is used when you want to output the values of variables into a character array/buffer. Its just like printf except that instead of the usual STDOUT, it outputs to the character buffer/arrray.

Have Fun

[Emmanuel Delaha]

I've found good use for sizeof() in such functions as snprintf. You never know when you're going to resize the buffer a little, and when you do, it can be a real pain to dig up all those hardcoded size limiters.

char buf[4];
snprintf ( buf, sizeof(buf), "%d\n", 10 );

It's fine ... as long as 'buf' is an array. Just keep in mind that an array decays to a pointer when passed to a function. An extra parameter for the size could be necessary for flexibility.

[Prelude]

I've found good use for sizeof() in such functions as snprintf. You never know when you're going to resize the buffer a little, and when you do, it can be a real pain to dig up all those hardcoded size limiters.

char buf[4];

snprintf ( buf, sizeof(buf), "%d\n", 10 );

This is a rather old thread...

[MortalMonkey]

Yeah sorry, but it was the 4th or 5th down when searching for "snprintf". Quite a shame, really.