#include <stdlib.h> // longest text line-- usage: maxrec filename
#include <stdio.h>
#include <sys/stat.h>
size_t filesize(int fd)  // file size in bytes
{
   struct stat st;
   return (fstat(fd, &st)==0)? st.st_size : 0;
}

int max_recsz(char *p, size_t len, FILE* in) // longest record
{
   int mx=0;
   fread(p, 1, len, in);   
   for(len=0; *p; p++, len++)   	
      if(*p=='\n')
      {
        mx=(len>mx)? len: mx;
        len=0;
      }   
   return mx;
}

int main(int argc, char **argv)
{
   FILE *in=fopen((argc<2)? "": argv[1], "r");
   size_t len=(in==NULL)? 0: filesize(fileno(in));
   char *p=(len>0)? calloc(1, len+1): NULL;
   if(p!=NULL)
      printf("%s %d\n", argv[1], max_recsz(p, len, in));
   else
      printf("%s %d: File error, bad file type, empty file\n", 
        (argc>1)? argv[1]: "",0);
   free(p);
   return !len;
}