Working print_it.c for Sam’s Teach Yourself C Programming in 21 days

It’ s always awesome being blessed with incorrect code snippets in beginner programming books. Luckily, I have enough sexy house music to work through anything (thank you radio 1!). If you’re looking for a working print_it.c example, look no further!

much thanks to: http://www.programmersheaven.com/mb/beginnercpp/367391/367391/newbie-programming-error/ – There are bunch of sites with code for print_it.c and programmersheaven.com was the only one that had working code.

code:

/* print_it.c-- This program prints a listing with line numbers! */
#include <stdlib.h>
#include <stdio.h>
void do_heading(char *filename);
int line = 0, page = 0;
int main( int argv, char *argc[] )
{
char buffer[256];
FILE *fp;
if( argv < 2)
{
fprintf(stderr, "\nProper Usage is: ");
fprintf(stderr, "\n\nprint_it filename.ext\n" );
return(1);
}
if (( fp = fopen( argc[1], "r" )) == NULL )
{
fprintf( stderr, "Error opening file, %s!", argc[1]);
return(1);
}
page = 0;
line = 1;
do_heading( argc[1]);
while( fgets( buffer, 256, fp ) != NULL )
{
if( line % 55 == 0 )
do_heading( argc[1] );
fprintf( stdout, "%4d:\t%s", line++, buffer );
}
fprintf( stdout, "\f" );
fclose(fp);
return 0;
}
void do_heading( char *filename )
{
page++;
if ( page > 1)
fprintf( stdout, "\f" );
fprintf( stdout, "Page: %d, %s\n\n", page, filename );
}
/* print_it.c-- This program prints a listing with line numbers! */#include <stdlib.h>#include <stdio.h>
void do_heading(char *filename);
int line = 0, page = 0;
int main( int argv, char *argc[] ){char buffer[256];FILE *fp;
if( argv < 2){fprintf(stderr, "\nProper Usage is: ");fprintf(stderr, "\n\nprint_it filename.ext\n" );return(1);}
if (( fp = fopen( argc[1], "r" )) == NULL ){fprintf( stderr, "Error opening file, %s!", argc[1]);return(1);}
page = 0;line = 1;do_heading( argc[1]);
while( fgets( buffer, 256, fp ) != NULL ){if( line % 55 == 0 )do_heading( argc[1] );
fprintf( stdout, "%4d:\t%s", line++, buffer );}
fprintf( stdout, "\f" );fclose(fp);return 0;}
void do_heading( char *filename ){page++;
if ( page > 1)fprintf( stdout, "\f" );
fprintf( stdout, "Page: %d, %s\n\n", page, filename );}

now all that’s left is:

gcc print_it.c -o print

./print print_it.c