1
vote
2answers
155 views

How to quieten tcpdump output when reading a pcap file?

I notice that when using tcpdump to read a pcap file, the tcpdump command somehow manages to print information to my console even when I redirect both STDOUT and STDERR. How can I prevent tcpdump from ...
-1
votes
1answer
124 views

what are the types of error messages that dd outputs? [duplicate]

What are the error messages that dd outputs? I tried to look at manual, but it does not say anything about it. Or I do not know how to look at manuals (man). Edit: OK. I'll make it simple: what error ...
2
votes
1answer
147 views

What happens if dd encounters errors while output of dd is being piped to gzip?

Suppose that dd if=/dev/sda bs=100M | gzip -c > somefile.img.gz is done. If errors occur in dd, do I get to see error messages in terminal, or do they get ignored? Also, suppose that dd ...
18
votes
3answers
1k views

Why does the output of some Linux programs go to neither STDOUT nor STDERR?

Why does the output of some Linux programs go to neither STDOUT nor STDERR? Actually, I want to know how to reliably capture all program output, no matter what 'stream' it uses. The problem I have is ...
3
votes
1answer
444 views

Why can I see password prompts through redirecting output?

So, I've got a command that I'm issuing that is essentially 'ssh'ing into various hosts: command 2&>1 | grep "desired output" Every once in a while, in the midst of the command, it'll run ...
1
vote
1answer
320 views

Redirecting to /dev/null and a file at the same time

I'm trying to execute the following command: find . -name ".[ch]" | xargs grep -in pattern > file There are some errors that are printed on stderr because a few files are not found. How can I ...
3
votes
3answers
1k views

Determine if output is stdout or stderr

How can I determine if what a process is outputting is stdout or stderr?
3
votes
2answers
357 views

Missing segfault output in Linux terminal when running with “&”

I am debugging an application that has to run with other components. I am wrapping everything in a script: #!/bin/bash ./component1 > 1.log & ./my_application & ./component2 > 2.log ...
0
votes
1answer
271 views

Linux : Rotating log buffer with output redirection

I have an application that prints errors on stderr. I can redirect that output to a file with app 2> log.txt (Un)fortunately I log tons of information. I'd like log.txt to not grow too much, or ...
1
vote
1answer
80 views

Formatting bash errors

I am using Fedora 14 and when I am executing a file: #!/bin/bash asd #assuming this command does not exist I am getting following error: /path/to/file: line 2: asd: command not found I want to ...
3
votes
1answer
1k views

How to tee to stderr? (multiple sinks in one pipeline)

some_source | (tee /dev/stderr | sink_1) 2>&1 | sink_2 Seems to fail. How to do it right without of any temporaries?