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Mail Archives: djgpp/1996/05/09/09:14:03

From: kagel AT quasar DOT bloomberg DOT com
Date: Thu, 9 May 1996 08:59:05 -0400
Message-Id: <9605091259.AA04851@quasar.bloomberg.com >
To: thunberg AT algonet DOT se
Cc: djgpp AT delorie DOT com
In-Reply-To: <318E71BD.904@algonet.se> (message from Rikard Thunberg on Mon, 06 May 1996 23:40:13 +0200)
Subject: Re: i/o file handling - integers
Reply-To: kagel AT dg1 DOT bloomberg DOT com

   From: Rikard Thunberg <thunberg AT algonet DOT se>
   Date: Mon, 06 May 1996 23:40:13 +0200

   What is the appropriate way to read/write integers from/to a file with the same size as it is stored in 
   memory, i.e. a long integer (32bit) would occupy 4 bytes in the file. I have reached a solution but it seems 
   rather clumsy:

   #include<stdio.h>
   void main()
   {
    FILE *fileh;
    unsigned long my_long=0x41424344;
    char *charpek;
    fileh = fopen("test.dat","wb");
    charpek= (char *) &my_long;
    fprintf(fileh,"%c%c%c%c",*charpek,*(charpek+1),*(charpek+2),*(charpek+3));
    fclose(fileh);
   }


Your right that's UGLY.  Try this:


#include<stdio.h>
void main()
{
    FILE *fileh;
    unsigned long my_long=0x41424344;
    short my_short = 123;

    fileh = fopen("test.dat","wb");

    fwrite( &my_long, sizeof my_long, 1, fileh );
    fwrite( &my_short, sizeof my_short, 1, fileh );

    fclose(fileh);
}


-- 
Art S. Kagel, kagel AT quasar DOT bloomberg DOT com

A proverb is no proverb to you 'till life has illustrated it.  -- John Keats

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