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copied!<p>You are doing everything right in regard of passing an array of pointers and allocating memory. What leading to a heap corruption is incorrect usage of <code>strncpy</code> function. The arrays where you are trying to copy data to are slightly smaller than <code>MAXBUFF</code> in all cases. To fix this, you have to specify the size of destination array instead of <code>MAXBUFF</code>. For example, instead of:</p> <pre><code>strncpy(tmpPtr->fullName,inRecord,MAXBUFF); </code></pre> <p>... do (assuming that buffer is already filled with <code>\0</code> symbols):</p> <pre><code>strncpy(tmpPtr->fullName,inRecord, sizeof(tmpPtr->fullName) - 1); </code></pre> <p>Also, using <code>gets</code> function is not recommended as well as it could easily lead to buffer overruns. Try using <code>fgets</code> instead.</p> <p>Here is your modified example that works:</p> <pre><code>#include <stdlib.h> #include <stdio.h> #include <string.h> #define MAXSTRUCTS 2 #define MAXBUFF 100 typedef struct { char fullName[41]; char address[41]; char cityState[41]; char zipcode[11]; } Persons; int readData(Persons *structPtrs[]); int main () { int totalStructs; int recs; Persons *structPtrs[MAXSTRUCTS]; totalStructs = 0; structPtrs[0] = NULL; totalStructs = readData(structPtrs); for(recs = 0; recs < totalStructs; ++recs) { printf ("Record #%d - %s\n", recs + 1, structPtrs[recs]->fullName); } return 0; } int readData(Persons *strptr[]) { int tStructs = 0; int recs; char inRecord[MAXBUFF]; Persons *tmpPtr; tStructs = 0; for (recs=0; recs < MAXSTRUCTS; ++recs) { memset (inRecord, 0, sizeof(inRecord)); if (fgets(inRecord, sizeof (inRecord) - 1, stdin)) { strptr[recs] = (Persons *)malloc(sizeof(Persons)); tmpPtr = strptr[recs]; memset (tmpPtr, 0, sizeof(Persons)); strncpy(tmpPtr->fullName,inRecord,sizeof(tmpPtr->fullName) - 1); fgets(inRecord, sizeof (inRecord) - 1, stdin); strncpy(tmpPtr->address,inRecord,sizeof(tmpPtr->address) - 1); fgets(inRecord, sizeof (inRecord) - 1, stdin); strncpy(tmpPtr->cityState,inRecord, sizeof(tmpPtr->cityState) - 1); fgets(inRecord, sizeof (inRecord) - 1, stdin); strncpy(tmpPtr->zipcode,inRecord, sizeof (tmpPtr->zipcode) - 1); strptr[recs] = tmpPtr; tStructs++; } else { if ( recs = 0 ) { exit (0); } recs=MAXSTRUCTS; } } return(tStructs); } </code></pre>

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