% commands

[MoNksBaNe_Agahnim]

I've been reading a lot recently and I keep coming across %<letter> commands....

example....

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[Pulled from 6.0 version of Greet Bot]

Send("%c%c%s\r\n%s\r\n", 0x03, 0x04, szLoginName, szPassword);



What exactly are these types of command, %c %s %d (may be others not sure)

Thanks for any and all help
- MBane_Agahnim

[Dante]

I don't know what %c and %s do, but I know what %d does.
heres some examples of shit:
scanf("%d", &bob);
in this case, when the user types in a decimal number, it will assign that number to the variable bob.
So now that we got that out of the way, that Send stuff sends the data.
Send("%d", bob);
That will send whatever you typed in at scanf.
Thats the only way I could explain it, maybe someone else can help you better.

[AC_Drkan]

Ok,

%c is individual characters like a, b, c, d

%s is a string of data like "i am cool"

Dan

[iago]

Look up printf(), scanf() style formatting.

[Eli_1]

%c Character 'a'
%d or %i -- Signed decimal integer 392
%e Scientific notation (mantise/exponent) using e character 3.9265e2
%f Decimal floating point 392.65
%g Use shorter %e or %f 392.65
%o Signed octal 610
%s String of characters sample
%u Unsigned decimal integer 7235
%x Unsigned hexadecimal integer 7fa
%p Address pointed by the argument B800:0000

[Mephisto]

I don't know what you mean by commands, but I think you're getting at operators.  But nontheless, they're neither.  They're format identifiers C uses to generally determine what type of variable it is going to be dealing with.  For instance, if you use %s, the function you're using with it that uses these format identifiers (printf, scanf, etc.) will expect a string.  Generally, the format identifiers go in quotes (e.g. printf("%d") or scanf("%d")) and the variable which you're going to be using that corresponds to that format identifier is not in quotes (e.g. printf("%d", theintgervar) or scanf("%d", &theintegervar)).  You should learn about what functions actually use these.  Generally, the concept/syntax is the same for any use of them, though.

[Skywing]

You can also specify things like the length of output, or the justification of it, etc.
The output format of %p is an exception to most of the standard printf codes in that it's output is implementation-dependent.

[Grok]

I think their terminology is 'format specifiers'.

[Mephisto]

Close enough.

[AC_Drkan]

let me give you some code to see what it does.

here its a combnation of different things just copy and paste it:

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#include <stdio.h>

void concat (char result[], char str1[], int n1, char str2[], int n2)
{
   int i, j;
   
   /* copy str1 to result */
   
   for ( i = 0; i < n1 ; ++i)
   result[i] = str1[i];
   
   /* copy str2 to result */
   
   for ( j = 0; j < n2 ; ++j)
   result[n1 + j] = str2[j];
}

int string_length (char string[])
{
   int count = 0;
   
   while ( string[count] != '\0')
   ++count;
   
   return (count);
}

main()
{
   void concat(char result[], char str1[], int n1, char str2[], int n2);
   int string_length (char string[]);
   char s4[81], s5[81], s6[81];
   char s1[6] = {'T', 'e', 's', 't', ' ', '\0'};
   char s2[7] = {'W', 'o', 'r', 'k', 's', '.', '\0'};
   char s3[13];
   int i;
   
   concat (s3, s1, 5, s2, 6);
   
   for ( i = 0; i < 11; ++i)
      printf ("%c\n", s3[i]);
      
   printf ("\n");
   
   printf ("%i %i \n", string_length(s1),  /* %c */string_length(s2));
   
   printf ("Enter Text Here: ");
   scanf  ("%s%s%s", s4, s5, s6); /* %s */
   printf ("\ns1 = %s\ns2 = %s\ns3 = %s\n\n", s4, s5, s6);
   
   printf ("\aSYSTEM SHUT DOWN IN FIVE MINUTES!!! \n");
}


Zak's edit: learn to use code tags please - and why on earth did you write your own versions of strlen and strcat? there are already perfectly good functions to perform concatenation and length determination

[iago]

Yes, and the standard strlen and strcat are much more efficient.

[Skywing]

I don't think his concat() will null terminate it with the arguments he gave.

[iago]

You're right.  Why would you ever need to specify lengths, anyway?

int i = 0, j = 0;
while(str1)
  result = str1[i++];
while(str2[j])
  result[i++] = str2[j++];
result = '\0';

Although the standard strcat() will still work better.

[Eibro]

I wonder what a strcat looks like.
Meow.

[Yoni]

I wonder what a strcat looks like.
Meow.