Hello

Your C code is broken somwhat, let's see:

extern char * danCGIReplacedCRLF(char * szFixMe){
    int i,j,iLen=0,iNewLen=0;
    int iCRLFcount=0;
    char* szResult=NULL;

    iLen=strlen(szFixMe);

    for (i=0;i<=iLen;i++){ /* this should be i < len */
        if (szFixMe[i]==(int) '\n' || szFixMe[i]==(int) '\r')
            iCRLFcount++;
            /* and here you're counting how many \r or \n
               you see, not how many "\r\n" sequences */
    }

/* you don't need the <p>+NULL+text, you need <p>+text */
// need space for first <p> +NULL+ text 
// + replace each CR &LF + last " <\p>"
    iNewLen=3+1+strlen(szFixMe)+(iCRLFcount*8)+5;
        szResult = malloc(iNewLen);

        if (szResult){
/* what's wrong with strcpy(szResult, "<p>"); ? */
        szResult[0]='<';
        szResult[1]='p';
        szResult[2]='>';
        szResult[3]='\0';
        i=0;
        j=3;

        while (i<=iLen)
            if (szFixMe[i]==(int) '\n' || szFixMe[i]==(int) '\r'){
  /* here again, you're checking for \r or \n, now the pair */
                strcat(szResult," </p><p>");
                j+=8;
/* and now I'm completely lost!, why are you looking for \n\r?  
I thought we were looking for \r\n. */
                // deal with Newline CR pairs
                if(szFixMe[i]==(int) '\n' && szFixMe[i+1]==(int) '\r'
                    || szFixMe[i]==(int) '\r' || szFixMe[i+1]==(int) '
+\n')
                    i+=2;
                else
                    i++;
            }else{
                szResult[j]=szFixMe[i];
                j++;
                szResult[j]='\0'; //dest string in strcat needs termin
+ating \0
                i++; 
            } //outer loop & if statement

//end of new document needs </p> to match at start
                strcat(szResult," </p>");
    } // if(szResult !=NULL )

    return szResult;
}
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Hmmm, I don't think this C code even comes closely to the Perl code given by you. Here one way to do it. This code aims to be simple and fast, rather than optimally fast. Enjoy :-).

/*********************************************************/
#if 0
we want to do the following:

sub MakePtag{
  my ($fixme)=@_;              # take in our parameters
  $fixme='<p>'.$fixme;         # Prepend a <p> tag to our string
  $fixme=~s|(\r\n)|</p><p>|g; # replace all \r\n with <\p><p>
  $fixme.='</p>';              # Append closing </p> tag
  return $fixme;                
}
#endif
char* make_p_tag(char* str){
    int len = 0;
    int cr = 0; /* this will tell you if we found \r */
    char *s = str;
    char *newstr, *s2;

    /* s#\r\n#<p></p>#, increases len by 5 (7-2)*/
    while(*s != '\0'){ /* while we have more data */
        ++len;
        if(*s == '\r'){
            cr = 1; /* we found one */
        } else if(*s == '\n' && cr){ 
            /* we found \n and \r in the prev step */
            cr = 0; /* forget we found a \r */
            len += 5;
        } else {
            cr = 0; /* also forget we found an isolated \r*/
        }
        ++s;
    }
    s = str;
    s2 = newstr = calloc(len+8, sizeof(char));
    strcpy(s2,"<p>");
    s2 += 3;
    while(*s != '\0'){
        *s2 = *s; /* copy this char to the output string */
        if(*s == '\r'){
            cr = 1; /* mark that we put a \r */
        } else if(*s == '\n' && cr){ /* now we placed \r\n */
            cr = 0;
            strcpy(s2-1,"</p><p>"); /* put </p><p> */
            s2 += 5; /* and advance */
        } else {
            cr = 0; /* forget it */
        }
        ++s;
        ++s2;
    }
    strcpy(s2,"</p>"); /* put terminating </p> */
    s2+=4;
    *s2 = '\0';
    return newstr;
}
[download]

Hope this helps.

PS: You need </P> not <\P>
PS2: I know this is the *Perl* monastery, but I thought this shouldn't hurt :-)

Update: meant to say strcpy instead of strcat:

/* what's wrong with strcpy(szResult, "<p>"); ? */
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