Hi, I'm currently writing a perl-wrapper for Debians aptitude. The wrapper should just color some parts of the output. If I want to install a package, aptitude usually asks 'Do you want to continue? [Y/n/?]' without appending a \n after the question. The problem is, that my wrapper does not display this question until I enter something at the keyboard. This looks as follows: 
...
Need to get 667kB of archives. After unpacking 3965kB will be used.
y
Do you want to continue? [Y/n/?] Writing extended state information...
...

[download]
The actual question is printed after my input. Currently, the executed code in the wrapper is very simple: 
print $_ while (<STDIN>);

[download]
To get the whole thing running, I pipe the output of aptitude into the wrapper: sudo aptitude install xyz | ./wrap.pl After playing around for a while now, I know that's a problem of buffering but I'm not sure how to bypass it.

Thanks

In reply to I/O buffering problem by pwr

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