Reading data from files

[krishna_v]

How to read data from files to structures(stru cture having more
elements)
Thanks in adavance

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[krishna_v]

Originally posted by Burne C

"krishna_v" wrote in message news:3150950.10 59105697@dbforu ms.-
comnews:31***** ***********@dbf orums.com...

How to read data from files to structures(stru cture having

more

elements)
Thanks in adavance
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http://dbforums.com/http://dbforums.com

If you write the structure to the file by yourself and you have to
read it later (on the same
machine), try this method :

#include

/* some structure */
typedef struct mystruct_tag
{
int var1;
int var2;
long var3;
}mystruct;

int main(void)
{
/* create a file */
FILE *fp = tmpfile();
mystruct mst1;
mystruct mst2 = {10,20,30};

/* write the structure */
fwrite(&mst2,si zeof(mystruct), 1,fp);

rewind(fp);

/* try to read it back */
fread(&mst1,siz eof(mystruct),1 ,fp);

printf("The struct contain %d %d %d
\n",mst1.var1,m st1.var2,mst1.v ar3);

fclose(fp);

return 0;

}

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[krishna_v]

Originally posted by Zoran Cutura

krishna_v wrote:

How to read data from files to structures(stru cture having

more

elements)

That pretty much depends on how the data is stored into the
file, which
is what people call file formats.
Note that structures cannot be portable written and read from a file
as blocks, because they may include system dependent stuff like
padding
bytes. So if you're talking about structure data that is written to a
file in binary as a block, you'll probably burn your fingers.
Store every element of the structure as a value of its own and read it
back is this.
--
Z (Zo**********@d aimlerchrysler. com)
"LISP is worth learning for the profound enlightenment experience
you will have when you finally get it; that experience will make you
a better programmer for the rest of your days." -- Eric S. Raymond

HI
Thank you.

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