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[QUOTE="somebody, post: 2873659"]
There are two files below named search.c and search.h.
In the for loop in search.c, the for loop never exits,
even if mystruct[i].field1 has no match.  Instead of
exiting the for loop it keeps going until it segfaults.
This seems to be related to the strcmp with the NULL
value.  There are 2 comments below that indicate
the segfaults.  I guess the question is, when there
is no match, how to I detect that and return without
a segfault?

-Thanks

SEARCH.C ----------------------------------------

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

#include "search.h"

int search(char * field1)
{
  int i = 0;

/* This is never = to NULL, even when no match for field1 */

for(i=0; mystruct[i].field1 != NULL; i++) {

if(strcmp(field1, mystruct[i].field1) == 0) {
      return(mystruct[i].numfield);
    }

/*THIS SEGFAULTS ALWAYS!!!!*/
    /*if (strcmp(mystruct[i].field1, NULL) == 0) {*/
    /*}*/

}

return(0);
}

int main(void) 
{ 
  int retval = 0;

/* THIS CAN CAUSE SEGFAULT TOO!!! */
  /*This works if you match, for example, CCC.  But if*/
  /*you change the CCC to say YYY, which is not in the*/
  /*struct, it segfaults.*/

char str[] = "CCC";

retval = search(str);

printf("retval = %d\n", retval);
  
  return 0; 
}

SEARCH.H -----------------------------

struct _mystruct 
{
  char field1[4];
  char field2[4];
  char field3[2];
  char field4[3];
  int  numfield;
};

struct _mystruct mystruct[] = 
{
  "AAA", "EEE", "R", "DF", 25,
  "BBB", "FFF", "R", "DF", 25,
  "CCC", "GGG", "R", "DF", 99,
  "DDD", "HHH", "R", "DF", 13,
};[/i][/i][/i][/i][/i]
[/QUOTE]

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