ifstream in Solaris acting strangely

[Kamran]

Hi,

I am having problem using std::ifstream in my code under solaris.
Everything works fine on linux but the same thing i.e.
trying to read a binary file and fill in a struct result in
complete junk. I use WorskShop 6.0 and my solaris version
is 9.

An "od -x" on my input file gives:

0000: 68 65 61 72 74 5f 70 72 6f 70 65 72 74 79 5f 76
0010: 65 72 73 69 6f 6e 5f 30 32 2e 30 30 00 00 00 03
0020: 00 00 00 03 00 00 00 00 c6 1c 3c 00 00 00 00 00
0030: 00 00 00 00 bc 23 d7 0a 3d cc cc c4 3d cc cc c4
0040: 3d cd 17 a9 00 00 00 65 00 00 00 65 00 00 00 47

I have the following struct:

struct cubeHeader
{
char version[28];
int Dimension;
float novalue;
float xO;
float yO;
float zO;
float xIn;
float yIn;
float zIn;
int gNodes[3];
int dummy;
};

cubeHeader header;


I open the binary file and read using:

#include <string>
#include <iostream>
#include <fstream>

cfile = new std::ifstream(filename.c_str(),ios::binary);
// filename is defined in the class

cfile->seekg(0, ios::beg);;
cfile->read(header.version,28);
cfile->read((char*)&header.dummy, intSize); // should be 3
cfile->read((char*)&header.Dimension, intSize); // should be 3
cfile->read((char*)&header.dummy, intSize); // should be 0
cfile->read((char*)&header.novalue, floatSize); // should be -9999
cfile->read((char*)&header.xO, floatSize); // should be 0
cfile->read((char*)&header.yO, floatSize); // should be 0
if (header.gridDimension == 3) {
cfile->read((char *)&header.zO, floatSize); // should be -0.1
}
cfile->read((char *)&header.xI, floatSize);
cfile->read((char *)&header.yI, floatSize);
if (header.gridDimension == 3) {
cfile->read((char *)&header.zI, floatSize);
}
for (int i = 0; i < header.gridDimension; i++) {
cfile->read((char *)&header.gNodes, intSize);
}


What I get is that the first byte in the file is read twice, i.e. my
header.version's byte 0 and 1 both have value 68 (see the input file
at the top) and the subsequent bytes are then (presumably) read wrong.
(it is infact complete bullocks)
Then I thought well I don't start from position 0 but position 1:
seekg(1, ios::beg). The result was that it didn't read the first byte
(as intended) but read the second byte twice (value 65). Still stranger,
those integer variables that followed the "version" part of the header
was read correctly but not the float variables !!!
I hate to admit that I am doing something stupid here though it often
turns out to be the case but could it be some compiler incompatibilty or
version or solaris and std library ? Any excuse at all ?

Thanks in advance

Kamran

 

[James Carlson]

What I get is that the first byte in the file is read twice, i.e. my
header.version's byte 0 and 1 both have value 68 (see the input file
at the top) and the subsequent bytes are then (presumably) read wrong.
(it is infact complete bullocks)
Then I thought well I don't start from position 0 but position 1:
seekg(1, ios::beg). The result was that it didn't read the first byte
(as intended) but read the second byte twice (value 65). Still stranger,
those integer variables that followed the "version" part of the header
was read correctly but not the float variables !!!
I hate to admit that I am doing something stupid here though it often
turns out to be the case but could it be some compiler incompatibilty
or
version or solaris and std library ? Any excuse at all ?

It sounds to me like a library bug. At a guess based on the symptoms,
something is mishandling an ungetc.

 

[Martin Steen]

Hi,

I am having problem using std::ifstream in my code under solaris.
Everything works fine on linux but the same thing i.e.
trying to read a binary file and fill in a struct result in
complete junk. I use WorskShop 6.0 and my solaris version
is 9.

Did you take care of the byte order?

Sun SPARC has a different byte order than Intel x86.
SPARC = Big endian or MSB, Intel x86 = little endian or LSB.

http://en.wikipedia.org/wiki/Byte_order

Best regards,
-Martin

 

[Larry Smith]

Hi,

I am having problem using std::ifstream in my code under solaris.
Everything works fine on linux but the same thing i.e.
trying to read a binary file and fill in a struct result in
complete junk. I use WorskShop 6.0 and my solaris version
is 9.

An "od -x" on my input file gives:

0000: 68 65 61 72 74 5f 70 72 6f 70 65 72 74 79 5f 76
0010: 65 72 73 69 6f 6e 5f 30 32 2e 30 30 00 00 00 03
0020: 00 00 00 03 00 00 00 00 c6 1c 3c 00 00 00 00 00
0030: 00 00 00 00 bc 23 d7 0a 3d cc cc c4 3d cc cc c4
0040: 3d cd 17 a9 00 00 00 65 00 00 00 65 00 00 00 47

I have the following struct:

struct cubeHeader
{
char version[28];
int Dimension;
float novalue;
float xO;
float yO;
float zO;
float xIn;
float yIn;
float zIn;
int gNodes[3];
int dummy;
};

cubeHeader header;


I open the binary file and read using:

#include <string>
#include <iostream>
#include <fstream>

cfile = new std::ifstream(filename.c_str(),ios::binary);
// filename is defined in the class

cfile->seekg(0, ios::beg);;
cfile->read(header.version,28);
cfile->read((char*)&header.dummy, intSize); // should be 3
cfile->read((char*)&header.Dimension, intSize); // should be 3
cfile->read((char*)&header.dummy, intSize); // should be 0
cfile->read((char*)&header.novalue, floatSize); // should be -9999
cfile->read((char*)&header.xO, floatSize); // should be 0
cfile->read((char*)&header.yO, floatSize); // should be 0
if (header.gridDimension == 3) {
cfile->read((char *)&header.zO, floatSize); // should be -0.1
}
cfile->read((char *)&header.xI, floatSize);
cfile->read((char *)&header.yI, floatSize);
if (header.gridDimension == 3) {
cfile->read((char *)&header.zI, floatSize);
}
for (int i = 0; i < header.gridDimension; i++) {
cfile->read((char *)&header.gNodes, intSize);
}


What I get is that the first byte in the file is read twice, i.e. my
header.version's byte 0 and 1 both have value 68 (see the input file
at the top) and the subsequent bytes are then (presumably) read wrong.
(it is infact complete bullocks)
Then I thought well I don't start from position 0 but position 1:
seekg(1, ios::beg). The result was that it didn't read the first byte
(as intended) but read the second byte twice (value 65). Still stranger,
those integer variables that followed the "version" part of the header
was read correctly but not the float variables !!!
I hate to admit that I am doing something stupid here though it often
turns out to be the case but could it be some compiler incompatibilty or
version or solaris and std library ? Any excuse at all ?

Thanks in advance

Kamran

This is a known bug in Forte 6. It is corrected in later versions.

 

[Kamran]

Did you take care of the byte order?

Sun SPARC has a different byte order than Intel x86.
SPARC = Big endian or MSB, Intel x86 = little endian or LSB.

http://en.wikipedia.org/wiki/Byte_order

Best regards,
-Martin

Thanks for the answer Martin. Yes I have made sure about that. But the
problem seems to be WS Forte 6.0 on Solaris. It is a bug there that I
have been told to have been fixed in the later versions. The order for
this has been placed and in the meantime I have to use the good old
FILE* in C.

regards

Kamran

 

[Kamran]

Hi,

I am having problem using std::ifstream in my code under solaris.
Everything works fine on linux but the same thing i.e.
trying to read a binary file and fill in a struct result in
complete junk. I use WorskShop 6.0 and my solaris version
is 9.

An "od -x" on my input file gives:

0000: 68 65 61 72 74 5f 70 72 6f 70 65 72 74 79 5f 76
0010: 65 72 73 69 6f 6e 5f 30 32 2e 30 30 00 00 00 03
0020: 00 00 00 03 00 00 00 00 c6 1c 3c 00 00 00 00 00
0030: 00 00 00 00 bc 23 d7 0a 3d cc cc c4 3d cc cc c4
0040: 3d cd 17 a9 00 00 00 65 00 00 00 65 00 00 00 47

I have the following struct:

struct cubeHeader
{
char version[28];
int Dimension;
float novalue;
float xO;
float yO;
float zO;
float xIn;
float yIn;
float zIn;
int gNodes[3];
int dummy;
};

cubeHeader header;


I open the binary file and read using:

#include <string>
#include <iostream>
#include <fstream>

cfile = new std::ifstream(filename.c_str(),ios::binary);
// filename is defined in the class

cfile->seekg(0, ios::beg);;
cfile->read(header.version,28);
cfile->read((char*)&header.dummy, intSize); // should be 3
cfile->read((char*)&header.Dimension, intSize); // should be 3
cfile->read((char*)&header.dummy, intSize); // should be 0
cfile->read((char*)&header.novalue, floatSize); // should be -9999
cfile->read((char*)&header.xO, floatSize); // should be 0
cfile->read((char*)&header.yO, floatSize); // should be 0
if (header.gridDimension == 3) {
cfile->read((char *)&header.zO, floatSize); // should be -0.1
}
cfile->read((char *)&header.xI, floatSize);
cfile->read((char *)&header.yI, floatSize);
if (header.gridDimension == 3) {
cfile->read((char *)&header.zI, floatSize);
}
for (int i = 0; i < header.gridDimension; i++) {
cfile->read((char *)&header.gNodes, intSize);
}


What I get is that the first byte in the file is read twice, i.e. my
header.version's byte 0 and 1 both have value 68 (see the input file
at the top) and the subsequent bytes are then (presumably) read wrong.
(it is infact complete bullocks)
Then I thought well I don't start from position 0 but position 1:
seekg(1, ios::beg). The result was that it didn't read the first byte
(as intended) but read the second byte twice (value 65). Still stranger,
those integer variables that followed the "version" part of the header
was read correctly but not the float variables !!!
I hate to admit that I am doing something stupid here though it often
turns out to be the case but could it be some compiler incompatibilty or
version or solaris and std library ? Any excuse at all ?

Thanks in advance

Kamran

This is a known bug in Forte 6. It is corrected in later versions.

and so it is. Thanks for the answer.

regards
kamran