Originally posted by: SystemAdmin

--------------------example1 begin---------------------------------
#include <sys/types.h>
#include <unistd.h>
#include <fstream>
#include <pthread.h>
#include <stdio.h>

char m_controlFile200 + 1 = "./log/control.ini";
std::fstream m_controlStream;
int readfile(int pid);
int main(int argc, char* argv[])
{
readfile(2);
}

int readfile(int pid)
{
int ret = 5;

m_controlStream.open(m_controlFile, std::ios:out);
printf("pid %d: opened up\n", pid, ret);

if (m_controlStream.fail())
{
printf("pid %d: open fail.\n", pid);
return -1;
}
else if (m_controlStream.bad())
{
printf("pid %d: open bad.\n", pid);
return -1;
}
else if (m_controlStream.eof())
{
printf("pid %d: open eof.\n", pid);
return -1;
}
else
{
m_controlStream << ret;
}
printf("pid %d: output is %d\n", pid, ret);
m_controlStream.close();
printf("pid %d: close\n", pid, ret);
for (int i = 0; i < 2; i++)
{
m_controlStream.open(m_controlFile);
printf("pid %d: opened up\n", pid, ret);
if (m_controlStream.fail())
{
printf("pid %d: open fail.\n", pid);
return -1;
}
else if (m_controlStream.bad())
{
printf("pid %d: open bad.\n", pid);
return -1;
}
else if (m_controlStream.eof())
{
printf("pid %d: open eof.\n", pid);
return -1;
}
else
{
m_controlStream >> ret;
}
printf("pid %d: output is %d\n", pid, ret);
m_controlStream.close();
printf("pid %d: close\n", pid, ret);
}
}
------------------------------example1 end--------------------------

------------------------------example2 begin------------------------
#include <sys/types.h>
#include <unistd.h>
#include <fstream>
#include <pthread.h>
#include <stdio.h>
char m_controlFile200 + 1 = "./log/control.ini";
std::fstream m_controlStream;
int readfile(int pid);
int main(int argc, char* argv[])
{
readfile(2);

}
int readfile(int pid)
{
int ret = 5;

m_controlStream.open(m_controlFile);
printf("pid %d: opened up\n", pid, ret);
if (m_controlStream.fail())
{
printf("pid %d: open fail.\n", pid);
return -1;
}
else if (m_controlStream.bad())
{
printf("pid %d: open bad.\n", pid);
return -1;
}
else if (m_controlStream.eof())
{
printf("pid %d: open eof.\n", pid);
return -1;
}
else
{
m_controlStream << ret;
}
printf("pid %d: output is %d\n", pid, ret);
m_controlStream.close();
printf("pid %d: close\n", pid, ret);
for (int i = 0; i < 2; i++)
{
m_controlStream.open(m_controlFile);
printf("pid %d: opened up\n", pid, ret);
if (m_controlStream.fail())
{
printf("pid %d: open fail.\n", pid);
return -1;
}
else if (m_controlStream.bad())
{
printf("pid %d: open bad.\n", pid);
return -1;
}
else if (m_controlStream.eof())
{
printf("pid %d: open eof.\n", pid);
return -1;
}
else
{
m_controlStream >> ret;
}
printf("pid %d: output is %d\n", pid, ret);
m_controlStream.close();
printf("pid %d: close\n", pid, ret);
}
}
-------------------------------example2 end--------------------------

under AIX5.1 run example2,output is:
pid 2: opened up
pid 2: output is 5
pid 2: close
pid 2: opened up
pid 2: output is 5
pid 2: close
pid 2: opened up
pid 2: output is 5
pid 2: close

under AIX5.1 run example2,output is:
pid 2: opened up
pid 2: output is 5
pid 2: close
pid 2: opened up
pid 2: output is 5
pid 2: close
pid 2: opened up
pid 2: open eof.
check the source of example1 and example2, we found the difference is:
Example1:m_controlStream.open(m_controlFile, ios:ut);
Example2:m_controlStream.open(m_controlFile);
who can tell me why?


#AIX-Forum

Originally posted by: nagger

Sorry, I can't tell you why but it seems the answer to lots of forum questions are have you tested this on the latest version of AIX and the latest maintenance level.

I note you are using AIX 5.1 - this release of AIX is so old it is not supported any longer without special additional service contracts.

Are you on the latest maintenance level? If not it could all be fixed already but don't forget to upgrade your firmware first.

#AIX-Forum