strcat: is there an ANTIstrcat!?

strcat joins two strings together but i wanted to know if there is a option that does the reverse.

i.e. if we had

Code:

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string1[] = "1, 2, 3, 4, 5, 6"

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and

Code:

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string2[] = "1, 2, 3"

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then the output would be

Code:

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5, 6

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in a new string.

anyone know of a method?

strtok, used with a little care.

strspn(stringa, stringb ) returns the offset of the first character in stringb that is not found anywhere in stringa.

strspn is non standard
A function like this shouldn't be too hard to implement yourself. Why don't you give it a go?

Quote:

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Originally Posted by sand_man

strspn is non standard
A function like this shouldn't be too hard to implement yourself. Why don't you give it a go?

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That's odd - It was part of the ANSI C89 standard. I don't have ISO C standard around. Has it been dropped - sounds unlikley.

Yep, its still there:

7.21.5.6

The strspn function

Synopsis

1 #include <string.h>
size_t strspn(const char *s1, const char *s2);

Description

2 The strspn function computes the length of the maximum initial segment of the string pointed to by s1 which consists entirely of characters from the string pointed to by s2.

Returns

3 The strspn function returns the length of the segment.

guys, thanks for the replies, i gave it a go and got partial success.

the problem is that the strtok deletes every occurance of a letter or number, i only want exact matches deleted.

otherwise its absolutely perfect

the is my attempt

Code:

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#include <stdio.h>
#include <string.h>

//***reads input one character at a time from the input stream
//  and puts into string called "uncoded"***//

char uncoded[BUFSIZ] = "#RAWWAASFRAMEA,COM1,9,68.0,SATTIME,1263,128186.000,000000000,58e4,1522,22,122,62,563456345dba43623443efdaef3245345fea325345626634623623c000,22*d04567cde";       

//char uncodedraaw[BUFSIZ] = "#RAWWAASFRAMEA, COM1, COM2,00000000, 58e4, 122, 22";

char uncodedraaw[BUFSIZ] = "#RAWWAASFRAMEA, SATTIME, COM1";

//  char *token;

char *decoded;


void main()

{

printf( "remaining data:\n" );

decoded = strtok( uncoded, uncodedraaw );

while( decoded != NULL )
  {
      /* While there are tokens in "string" */
      printf( " %s", decoded );
      /* Get next token: */
      decoded = strtok( NULL, uncodedraaw );
  }

}

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Quote:

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Originally Posted by jim mcnamara

That's odd - It was part of the ANSI C89 standard. I don't have ISO C standard around. Has it been dropped - sounds unlikley.

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Sorry for the false information, I had a quick glance but couldn't find it so I thought it was non standard.