fwrite in Linux and UNIX


 
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Top Forums Programming fwrite in Linux and UNIX
# 8  
Old 08-12-2008
I have checked the return code also. It is success only.
But i am not sure how to get the same output in both OS's

regards
rkraj
# 9  
Old 08-12-2008
I am leaning towards era's explanation that it's either compiler differences or endianess of the machine.
# 10  
Old 08-13-2008
I checked the fwrite both in Linux and UNIX, the number of items written is the same in both .

Regards
rkraj
# 11  
Old 08-13-2008
Can you pare down the program to a bare minimum, and compare a hex dump of its output on both platforms? Put an int, a string, and a float in a simple structure and write that to disk. Compare the resulting files by running a hex dump and analyzing what's where in that.
# 12  
Old 08-13-2008
I took a simple structure like the below.
It is very clear that the cksum vary here also.

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

struct temp
{
int a;
float f;
char name[20];
};
struct temp t1;
int main()
{
t1.a=10;
t1.f=89.798;
strcpy(t1.name,"TESTING\n");
int file_return;
FILE *fptr=NULL;
fptr=fopen("temp.text","w");
file_return= fwrite(&t1, sizeof(struct temp), 1,fptr);
cout<<"FILE_Return= "<<file_return;
fclose(fptr);
}
# 13  
Old 08-13-2008
And the hexdump we requested ...?
# 14  
Old 08-13-2008
Sorry about that

in Linux version the od -xc gives

0000000 000a 0000 9893 42b3 4554 5453 4e49 0a47
\n \0 \0 \0 223 230 263 B T E S T I N G \n
0000020 0000 0000 0000 0000 0000 0000
\0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
0000034

In HP-UX version it gives the answer as

0000000 0000 000a 42b3 9893 5445 5354 494e 470a
\0 \0 \0 \n B 263 230 223 T E S T I N G \n
0000020 0000 0000 0000 0000 0000 0000
\0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0 \0
0000034


Regards
rkraj
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