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Problems with redirection

I have this comand

xxx > file.txt

after that there many persons doing something like

tail -f file.txt


My problem is that the command sends litle messages and is not imediatly write to the file. There is any way to redirection imediatly write to the text file the output of the command.

I don't have admin premictions.
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oleber
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oleber
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1 Solution
 
chris_calabreseCommented:
The problem is likly that the xxx program uses the C stdio library, which knows the data is going to a file and buffers it.

Try
xxx | cat > file.txt
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oleberAuthor Commented:
I'm using this code

perl -e 'for ($i=0; $i<100000; $i++) {print "$i\n";if ($i % 1000 == 0){sleep 1}}' | cat > lixo.txt & ; tail -f lixo.txt

So just must stop if $i end's on 000, it stops in diferent values



My unix version

> version
Machine hardware:   sun4u
OS version:         5.6
Processor type:     sparc
Hardware:           SUNW,Ultra-4

...
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chris_calabreseCommented:
How busy is the machine? Maybe the job just isn't running continuously. Try a bigger sleep so you can tell the difference between machine business and intentional sleeps.

If this is buffering problem, you'll see things like the output being cut in the middle of a line.
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oleberAuthor Commented:
It's what is happening. The numbers are beeing cut in the middle of a line.
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ahoffmannCommented:
perl -e '$|=1;for ($i=0; $i<100000; $i++){print "$i\n";if ($i % 1000 == 0){sleep 1}}' | cat > lixo.txt & ; tail -f lixo.txt
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oleberAuthor Commented:
sorry, i full you with the code
perl -e '$|=1;for ($i=0; $i<100000; $i++){print "$i\n";if ($i % 1000 == 0){sleep 1}}'

What I have is a C/C++ program, the perl just sorce was an example of a command.

please, is there a way of doing something similar to $|=1 in C/C++.
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ahoffmannCommented:
fflush()
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chris_calabreseCommented:
and/or setbuf()
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tfewsterCommented:
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