02-15-2011
> Corona688
> achenle
Thank you for answering my question.
Quote:
This is what we call a 'race condition'. It's not an error condition, but you're not likely to get what you wanted either.
is that mean, in the other words, when fread/fwrite called at the same time on same chunk of the file, both function call doesn't return an error but the result of fread would be unpredictable...is that right?? it means result of fwrite is not affected by the fread function call?
Quote:
To make this situation predictable one should use file area locks, or mutexes, and so forth.
Okay. I will
Quote:
Both fread() and fwrite() by default buffer IO within the process's address space, so the OS may not even know that the application has made either call.
So actual device I/O may not occur at the same time as fwrite/fread function is called, isn't it? Can I trust operating system to sync the data passed to fwrite on the disk certainly in spite of the fact that fread is called simultaneously? (Of course, unless somebody pull out the plug of the computer before operating system sync the data in the buffer...)
now I think that I almost understand what happening behind the fread/fwrite anyway.
Thanks.
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LEARN ABOUT SUNOS
install-solaris
install-solaris(1M) install-solaris(1M)
NAME
install-solaris - install the Solaris operating system
SYNOPSIS
install-solaris
install-solaris invokes the Solaris Install program. Depending on graphical capability and available memory at the time of invocation,
install-solaris invokes either a text-based installer or a graphical installer.
The following minimum requirements for physical memory dictate which features are available during installation:
For SPARC machines:
128 MB
Minimum physical memory for all installation types
128 MB
Minimum physical memory required for windowing system
384 MB
Minimum physical memory required for graphical-based installation
For x86 machines:
256 MB
Minimum physical memory for all installation types
256 MB
Minimum physical memory required for windowing system
512 MB
Minimum physical memory required for graphical-based installation
In some cases, even if the minimum physical memory is present, available virtual memory after system startup can limit the number of fea-
tures available.
install-solaris exists only on the Solaris installation media (CD or DVD) and should be invoked only from there. Refer to the for more
details.
install-solaris allows installation of the operating system onto any standalone system. install-solaris loads the software available on the
installation media. Refer to the for disk space requirements.
Refer to the for more information on the various menus and selections.
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcdrom (Solaris instal- |
| |lation media) |
+-----------------------------+-----------------------------+
|Interface Stability |Evolving |
+-----------------------------+-----------------------------+
pkginfo(1), install(1M), pkgadd(1M), attributes(5)
It is advisable to exit install-solaris by means of the exit options in the install-solaris menus.
23 Sep 2005 install-solaris(1M)