> Perhaps I'm making some newbie, bonehead mistake here, but
> I can't see what it is.  I wrote a simple program which
> writes a table of celsius-to-fahrenheit conversions.
> I've included the entire program at the bottom of this post
> for reference, but the guts of the program are the following
> lines:

>   printf("    Fahr        Cels\n");

>   for (Fahr = FahrMin; Fahr <= FahrMax; Fahr += FahrInc)
>   {
>      Cels = (((Fahr-32)*100.0)/180.0);
>      printf("%10.3f   %10.3f\n", Fahr, Cels);
>   }

> When I run "CelsFahr 40 41 0.2, I expected it to print:

>    Cels        Fahr
>    40.000      104.000
>    40.200      104.360
>    40.400      104.720
>    40.600      105.080
>    40.800      105.440

> but what it *actually* prints is:

>    Cels        Fahr
>    40.000      104.000

>    40.200      104.360

>    40.400      104.720

>    40.600      105.080

>    40.800      105.440

> Why the extra blank lines?  printf() doesn't automatically
> print a newline, does it?  Don't you have to put those in
> manually?  So I don't see why I'm getting extra blank lines.
> Am I missing something obvious?

> What about just doing printf ("abc\ndef\n"); ?

> Or puts("abc"); puts("def"); ?

> (I'm assuming the display width is more than about 24 characters.)

>    printf("    Fahr        Cels\n");

>    for (Fahr = FahrMin; Fahr <= FahrMax; Fahr += FahrInc)
>    {
>       Cels = (((Fahr-32)*100.0)/180.0);
>       printf("%10.3f   %10.3f\n", Fahr, Cels);
>    }

> When I run "CelsFahr 40 41 0.2, I expected it to print:

>     Cels        Fahr
>     40.000      104.000
>     40.200      104.360
>     40.400      104.720
>     40.600      105.080
>     40.800      105.440

> but what it *actually* prints is:

>     Cels        Fahr
>     40.000      104.000

>     40.200      104.360

>     40.400      104.720

>     40.600      105.080

>     40.800      105.440

> Why the extra blank lines?  printf() doesn't automatically
> print a newline, does it?  Don't you have to put those in
> manually?  So I don't see why I'm getting extra blank lines.
> Am I missing something obvious?

> Entire program, for reference:

> /********************************************************************\
>  * Program name:  FahrCelsTable                                     *
>  * Description:   Fahrenheit-to-Celsius Table Generator             *
>  * File name:     fahrcelstable.c                                   *
>  * Source for:    fahrcelstable.exe                                 *
>  * Author:        Robbie Hatley                                     *
>  * Date written:  Sat May 01, 2004                                  *
>  * Inputs:        Three CLI args: begin, end, increment.            *
>  * Outputs:       Sends chart to cout.  Can be redir'ed to a file.  *
>  * To make:       No dependencies.                                  *
>  * Edit history:                                                    *
>  *   Thu Nov 23, 2006: Split FahrCelsTable from FahrCels.           *
> \********************************************************************/

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

> void Help (void);

> int main(int Fred, char* Ethel[])
> {
>    double FahrMin=0, FahrMax=0, FahrInc=0, Fahr=0, Cels=0;

>    if ( 2 == Fred && ( 0 == strcmp(Ethel[1], "-h") || 0 == strcmp(Ethel[1], "--help") ) )
>    {
>       Help();
>       return 777;
>    }

>    if (4 != Fred)
>    {
>       printf("FahrCelsTable must have 3 args.:\n");
>       printf("  Fahrenheit Min\n");
>       printf("  Fahrenheit Max\n");
>       printf("  Fahrenheit Increment\n");
>       return 666;
>    }

>    FahrMin = atof(Ethel[1]);
>    FahrMax = atof(Ethel[2]);
>    FahrInc = atof(Ethel[3]);

>    if (FahrMin > FahrMax - 0.001)
>    {
>       printf
>       (
>          "Error: maximum must be at least 0.001 greater than minimum.\n"
>       );
>       return 666;
>    }

>    if (FahrInc < 0.001)
>    {
>       printf
>       (
>          "Error: increment must be at least 0.001\n"
>       );
>       return 666;
>    }

>    printf("    Fahr        Cels\n");

>    for (Fahr = FahrMin; Fahr <= FahrMax; Fahr += FahrInc)
>    {
>       Cels = (((Fahr-32)*100.0)/180.0);
>       printf("%10.3f   %10.3f\n", Fahr, Cels);
>    }

> }

> void Help (void)
> {
>    printf
>    (
>       "FahrCelsTable must have 3 arguments:\n"
>       "  Fahrenheit Min\n"
>       "  Fahrenheit Max\n"
>       "  Fahrenheit Increment\n"
>       "Max must be at least 0.001 greater than Min,\n"
>       "and Increment must be at least 0.001\n"
>       "FahrCelsTable will then print a table of Fahrenheit-to-Celsius conversions\n"
>       "for the range and increment you specified."
>    );
>    return;

> }

> --
> Cheers,
> Robbie Hatley
> lonewolf at well dot com
> www dot well dot com slant tilde lonewolf slant

>      Cels        Fahr
>      40.000      104.000

>      40.200      104.360

> "bartc" wrote:

>> What happens when you leave out the "\n"?

>> What about just doing printf ("abc\ndef\n"); ?

>> Or puts("abc"); puts("def"); ?
> Ok, I'll test those.  Here's a simple program:
>   printf("abcd");
>   printf("efgh");
>   printf("ijkl");
...
> OUTPUT:

> abcdefghijkl
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> abc
> def

> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> abc
> def

> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

> printf() isn't automatically inserting newlines.
> I didn't think it would, as other programs I've written
> and compiled on same compiler don't put them in.