Parse string using strstr or strch

[spining123]

Question: How do you parse this string separating $a, $b, $c, and $d, into separate new fields. I know I will need to declare the field’s names; but not should of using the strstr or strch to separate the fields.

Example of the table:

typedef struct
{
char fieldA[50];
char fieldB[200];
} hrgtable;

tableA tabA[] = {
"1 $aSome data in field A","111$bPart1 of fieldB$cPart2 of fieldB$dPart3 of fieldB”,
"2 $aSome data in field A","222$bPart1 of fieldB$cPart2 of fieldB$dPart3 of fieldB”,
"3 $aSome data in field A","333$bPart1 of fieldB$cPart2 of fieldB$dPart3 of fieldB”,
};

Example of the code to parse string:

if (( m = strstr(tabA.fieldB,"$c")) !=NULL)
{
len = m - (tabA.fieldB);

printf("Testing... what's in m ^^^%s^^^\n",m);

This is what’s m… $cPart2 of fieldB$dPart3 of fieldB

I just want the string data starting at $c and ending at $d.
I did the following to copy the data starting at $d into n.

n = strchr(m,'$');
printf("Testing... what's in n ^^^%s^^^\n",n);
This is what’s n… $dPart3 of fieldB

I’m trying to get the data starting at $c and ending at $d strcat to textout.

strcat(textout,n - m);
};

I get the error message:
1506-280 (W) Function argument assignment between type
s "const unsigned char*" and "long" is not allowed.

Thank you in advance for your help.

 

[xwb]

n - m is a char* - char* which will give you an int. I think you want

strncat (textout, m, n -m);

Alternatively, if the code is non-reentrant and does not need to be thread safe, you could use strtok.

beforeBdol = strtok (m, "$") + 1;
beforeCdol = strtok (NULL, "$") + 1;
beforeDdol = strtok (NULL, "$") + 1;
strcat (textout, beforeCdol);

 

[spining123]

Thank you xwb,
I learned something new today (strtok).
I used the strtok as suggested and it resulted my problem. Again, thank you...

 

[DaveSinkula]

I'm not fond of [tt]strtok[/tt] because it modifies the original string. Toying with this, here is another approach.

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

int foo(char *dest, int size, const char *field, const char *delim)
{
   const char *end, *start = strstr(field, delim);
   if ( start != NULL )
   {
      start += strlen(delim);
      end = strchr(start, *delim);
      if ( end != NULL )
      {
         int length = end - start;
         if ( length >= --size )
         {
            length = size;
         }
         sprintf(dest, "%*.*s", length, length, start);
         return 1;
      }
   }
   return 0;
}

struct hrgtable
{
   char fieldA[50];
   char fieldB[200];
};

struct hrgtable tabA[] =
{
   {"1 $aSome data in field A","111$bPart1 of fieldB$cPart2-1 of fieldB$dPart3 of fieldB"},
   {"2 $aSome data in field A","222$bPart1 of fieldB$cPart2-2 of fieldB$dPart3 of fieldB"},
   {"3 $aSome data in field A","333$bPart1 of fieldB$cPart2-3 of fieldB$dPart3 of fieldB"},
};

int main(void)
{
   size_t i;
   for ( i = 0; i < sizeof tabA / sizeof *tabA; ++i )
   {
      char buffer[32];
      if ( foo(buffer, sizeof buffer, tabA[i].fieldB, "$c") )
      {
         puts(buffer);
      }
   }
   return 0;
}

/* my output
Part2-1 of fieldB
Part2-2 of fieldB
Part2-3 of fieldB
*/

 

[spining123]

Thanks so much for your help. You guys are great!