Hello I need to write and read a parameter through a file to get
communication between two processes.
I know how to use fopen, fprintf. But I wonder how can I overwrite the
old files.
For instance, I need to write the value of A into a file. Another
process need to access the data of A.
Then the first process will overwrite the value of A.
How can I do that?
Thanks a lot!
5  1615  po***********@g mail.com wrote: Hello I need to write and read a parameter through a file to get
communication between two processes.
I know how to use fopen, fprintf. But I wonder how can I overwrite the
old files.
For instance, I need to write the value of A into a file. Another
process need to access the data of A.
Then the first process will overwrite the value of A.
Do a
rewind (file);
before you use fprintf() on the file.
- Logan po***********@g mail.com wrote: Hello I need to write and read a parameter through a file to get
communication between two processes.
I know how to use fopen, fprintf. But I wonder how can I overwrite the
old files.
For instance, I need to write the value of A into a file. Another
process need to access the data of A.
Then the first process will overwrite the value of A.
How can I do that?
Thanks a lot!
As you have tried to do it, what problems do you have?
--
Joe Wright
"Everything should be made as simple as possible, but not simpler."
--- Albert Einstein --- po***********@g mail.com wrote: Hello I need to write and read a parameter through a file to get
communication between two processes.
I know how to use fopen, fprintf. But I wonder how can I overwrite the
old files.
For instance, I need to write the value of A into a file. Another
process need to access the data of A.
Then the first process will overwrite the value of A.
How can I do that?
Thanks a lot!
Insted of using files for giving communication between two process, you
can use either sockets or shared memory to do that
Best Regards,
Abdur
In article <11************ **********@z14g 2000cwz.googleg roups.com>, ab********@yaho o.co.in <ab********@yah oo.co.in> wrote:
.... Insted of using files for giving communication between two process, you
can use either sockets or shared memory to do that
Allow me to be the first to say this - and I say it from the deepness of my
heart, with all the kindness and love one has come to associate with the
helpful posts you get in this newsgroup:
Not portable. Can't discuss it here. Blah, blah, blah.
On 18 Jan 2006 20:42:18 -0800, "ab********@yah oo.co.in"
<ab********@yah oo.co.in> wrote in comp.lang.c:
po***********@g mail.com wrote: Hello I need to write and read a parameter through a file to get
communication between two processes.
I know how to use fopen, fprintf. But I wonder how can I overwrite the
old files.
For instance, I need to write the value of A into a file. Another
process need to access the data of A.
Then the first process will overwrite the value of A.
How can I do that?
Thanks a lot!
Insted of using files for giving communication between two process, you
can use either sockets or shared memory to do that
The C language does not have sockets or shared memory. If your
platform does, it is a non-standard extension. And just because your
platform does, it does not mean that the OP's platform has the same
non-standard extensions.
And by the way, non-standard extensions are off-topic here.
--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://c-faq.com/
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.l earn.c-c++ http://www.contrib.andrew.cmu.edu/~a...FAQ-acllc.html This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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