Re^3: Autoflush fails

Autoflush is something you do in your program, to control the output of your program , not something you can do to other programs

Other than changing your invocation (sudo ... ) there is nothing you can do

You say sudo ... works from bash, but does sudo ... |perl -pe 1 work the same?

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Re^4: Autoflush fails by sophate (Beadle) on May 31, 2012 at 04:23 UTC
Really appreciate your help :-) The results of "sudo tcpdump" are redirected to STDOUT right away. `,"sudo /usr/sbin/tcpdump -i eth3 host 226.1.109.109 2> +/dev/null"` [download] However, the results are buffered if I pipe it to "perl -pe 1" `,"sudo /usr/sbin/tcpdump -i eth3 host 226.1.109.109 2> +/dev/null \| perl -pe 1"` [download] Any alternative to a file handle to get the sudo resluts from a pipe?	[reply] [d/l] [select]
Re^5: Autoflush fails by Anonymous Monk on May 31, 2012 at 05:31 UTC
However, the results are buffered if I pipe it to "perl -pe 1" You'll find they're probably buffered if you pipe to anything ( even cat ) So the solution is to ddg://tcpdump buffered and find tcpdump: Re: pipeline buffering which says if you don't specify -w, -U means "flush the standard output after the information for each packet is printed" So there you have it, install sufficiently modern version of tcpdump that comes with -U option that flushes more often FYI there also exists pcapdump, Net::Pcap::Easy... Tutorials: Network Programming: Perl and Net::Pcap	[reply]