see these simple commands:
Code:
# dbus-monitor --system >> /data/eject.txt
This one works as expected ... dbus-monitor never terminates and whenever it outputs new lines, they are
[code]....
I'm trying to redirect nc command output but I can't do it.
I have tried this:
And this:
But it seems doesn't work.
I need to find one RUNNING word in latest created logs.
and as soon as i will get RUNNING WORD , i have to execute another Unix Command.
I wrote following script code...
Is there already a program that reads multiple pipes or file descriptors and writes to the standard output (not splitting lines).Like cat, but reading all files simultaneously and preserving lines.It is needed to avoid coding of select/epoll loops or using multithreading in simple programs. Like "select loop for bash".
View 1 Replies View RelatedI have a program that writes to stdout. Is there a way that I can redirect the output to the linux diff command or do I have to write the output to a file and then compare that. For example I have a bunch of test input files for a program and the corresponding expected output in another set of files. And I'd like to do something like ./program < t1.input | diff t1.expected.
View 3 Replies View RelatedI'm working on some scheduled task script files to keep nightly backups of some of our database information in place, and it's a bit annoying when they blow up. I know how to redirect stdout and stderr to a flat file I can view when I come in, and I know that 2>&1 maps them both to the same file (whatever was named in 1). However, I'm running into some cron-time situations where it's easier to have the two streams together, and other cron-time situations where it's easier to have them separated. I can't really tell which is going to happen; is there some way I could create both kinds of output file for my scripts, so that I've got a std_err only file and an interleaved std_out/std_err file?
Note: I've looked at the 'tee' command, but I don't think it will work for what I'm after. 'tee' appears to only work with stdout; I'm trying to work with stderr.
recently I had been to interview where I had a question to be answered, that what are advantages and disadvantages when desiging an application in linux.
View 1 Replies View RelatedI have an X11 GTK program, let's name it "foo".I would like to start it from command line, either from a text console, or from an ssh log-in. I want to run foo with Administrator privileges and in higher priority, and I need redirect standard output and standard error. Standard errors must go to syslog, except "libglade Warning" messages and empty line messages. Standard output is redirected to a file.I wrote a script, called "foo-start". The "foo" program must run continously, so the "foo-start" script should not wait for "foo"'s termination.The scrip actually looks likelike this:
cd "FOO'S DIR"
(sudo nice --10 ./foo --display=localhost:0 &) 3>&1 1>foo-output.log 2>&3 | grep . | grep -v lobglade-WARNING | loggerr -p local7.err -t foo &
[code]....
I am always confused about the redirection operator <Lets say i have a file input.txt that contains one word "hello" without the quotes when i do the following why don't i see any output? $echo < input.txt Secondly, i am slightly confused between input redirection < and pipe | operator. Sometimes they seem to do the same thing. For example i can achieve the output from the above command as follows $ cat input.txt | xargs echo
View 2 Replies View RelatedWhen I execute the following command from the linux command line I get the output I want to the screen
[Code]...
Within a bash script, I'm attempting to redirect file descriptors with exec, e.g. exec 3>&1 1>&2; however, I'd like to do something like exec $FD>&1 1>&2, which doesn't work because bash tries to execute the value of $FD. Various placements of eval fail, as well. Is there a way around this, or am I stuck hard-coding the descriptor?
View 3 Replies View RelatedI have this piece of code in my shell script file:
Code:
useradd $UserName; passwd <& $password
I am not able to perform Input Redirection while setting password programatically- without any user intervention.
I think there is a way to do it, but it is just getting slipped from my mind at the moment.
I'm writing a script to execute bash commands in the PHP CLI. I would like to suppress errors from bash and write my own error message if an error occurs. So far I have this (assuming log.txt doesn't exist!):
Code:
tac log.txt 2>/dev/null
Which works as expected, tac kicks up an error but the error is suppressed, but when I use this:
Code:
tac < log.txt 2>/dev/null
I get:
Code:
bash: log.txt: No such file or directory
The tac error is suppressed but bash still gives me a dirty error.
I've been using pipes and redirects for a long time and just realized that I don't know exactly how they are different. I just know that if you want to store the output in a file, then you use >. Otherwise most of the time you just use |. difference between pipes and redirects?
View 1 Replies View RelatedAlthough this is a basic stuff, but still i wonder.
Consider these two examples. code...
I wonder, why doesn't redirection work in first case? when to use redirect and when to use pipes? I have been Linux for a long time, but still this basic stuff baffles me.
File descriptors with pipes-Can someone help me with this three situations, what would happen?
a) a process open the same file twice and read through two file descriptors
b) a process does fork and both parent- and child-processes read parallell
c) two processes opens and read from same file.
has anyone seen this before, when running an ssh command as normal user via ssh i get results:
ssh picolo 'ls -d /var/sadm/pkg/* | egrep "Prod|Dev|UAT" |cut -d/ -f5;uname -r;grep -v "^#" /opt/Tivoli/lcf/dat/1/DMXAdaptiveFileSystem.dat'>>sshnotroot
and it creates file
more sshnotroot
Prod
5.10
[Code]...
I have two sources of internet which I want to share and balance the load on. With one source it's easy: plug it into the wireless router and Bob's your uncle. But how would you handle two sources and get load balancing? A switch? Would that really share the load?
View 4 Replies View RelatedHow to create and use named pipe on linux network.ie
client - my linux machine
server - my fren's linux machine
how to communicate between these two using named pipe created in C? do u have any similar code snippet written in C??
i got one server client application,its working fine on my machine.So i want enhance that code for networking.so help in this...
I have three machines networked to my desktop which run a bunch of simulations in parallel. As they're running, I connect to them via SSH and screen to keep an eye on the runs and look at the output. They stay usually connected for days at a time. The SSH servers and client are running Fedora 14. Yesterday one of my coworkers accidentally yanked the plug on one of the servers while it was running. When I powered it up again, I started getting some odd connection problems. I couldn't connect to it via SSH initially because I got the Remote Host Identification Changed (RSA host key changed) error. I deleted the key in .ssh/known_hosts, which allowed me to connect, but it denied my password. I then logged into that machine locally, restarted sshd, and removed .ssh/known_hosts again. Now I can log in via SSH without problems. However, the connection dies with a "Write failed: Broken pipe" error every few minutes (as opposed to the other two machines, which stay connected indefinitely).
So my questions are:
1.) why would a power loss affect the behavior of the SSH server?
2.) why do I keep getting broken pipes now?
As i am new to C++ i couldn't figure out how to input a file and make some change on the file and produce a output file. like this problem i have is.
"Program that processes an input file and produces an output file. The input file will contain lines of data, each containing two floating point numbers. The lines of the output file should contain the two numbers read and their average (with a '$' sign and 2 places after the decimal point)."
I have a file with something like** The total time for processing is 1245 seconds *when I doawk 'BEGIN{FS="The total time for processing"} {print $2 } ' fileI get correctly on screen 1245 seconds *but when I try to direct this to a file awk 'BEGIN{FS="The total time for processing"} {print $2 } ' file > outputthenoutput is empty ie the 1245 seconds * is not saved in ...Know why?
View 4 Replies View RelatedWith the command "tail -300 /var/log/apache2/access.log | less" i can look in the log for the 300 latest visitors. and i wanted to ask if it's possiblle to get that command to run from a php file and if yes how ?
View 4 Replies View RelatedLex's (actually Flex) output contains this:
Code:
#ifdef __cplusplus
extern "C" int yywrap (void );
[code]...
I am trying to learn C Programing and I'm having trouble on the output of my script. my script should count the characters in input but it doesn't give me any numbers..
here's my program code:
Code:
#include <stdio.h>
main()
{
double nc;
[code]....
i am having problem with displaying my text. my text file is displayed in such a way and is called test.......
Code:
Sam Worthington ... Jake SullyasZoe Saldana ... NeytiriasSigourney Weaver ... Dr. Grace AugustineasStephen Lang ... Colonel Miles QuaritchasJoel Moore ... Norm Spellman (as Joel David Moore)asGiovanni Ribisi ... Parker SelfridgeasMichelle Rodriguez ... Trudy ChaconasLaz Alonso ... Tsu'teyasWes Studi ... EytukanasCCH Pounder ... MoatasDileep Rao ... Dr. Max PatelasMatt Gerald ... Corporal Lyle WainfleetasSean Anthony Moran ... Private FikeasJason Whyte ... Cryo Vault Med TechasScott Lawrence ... Venture Star Crew Chiefmore
What i am trying to do is for the program to read "as" and then from there start a new line... thus the expected output is...
Code:
Sam Worthington ... Jake Sully
Zoe Saldana ... Neytiri
Sigourney Weaver ... Dr. Grace Augustine
[code]....
I keep getting the error saying ...
Code:
editmain.cpp.98:error: initializer fails to determine size of 'str'
what does this mean, and how can i be able to format my file in the way i want?
have a file (called it A) contains;
hostname 192.168.23.65
hostname 10.18.13.253
hostname 10.18.16.253
[code]...
See the first program below :
Code:
This code when compiled gives the following errors:
1. conflicting types for 'fun' at line no: 9
2. previous declaration of 'fun' was here at line no: 3
Why is this happening?
If i modify the above program as shown in the second program below:
Code:
This code when compiled gives no errors.
Why the difference occurs between the first and second program?
is there a way in code to tell SDL to be directed to another desktop? This is so I can full screen debug rather than running in windowed mode. By other desktop I don't mean other machine just another workspace.*
* sorry don't know correct term for this it seems in Debian you have 4 you can select from the low right of the desktop, seems to be called desktop 1-2 in ubuntu.
I have a script that generates a bunch of output, including the expansions details provided by: set -v -xI am trying to pipe everything that is displayed to a file, in addition to displaying it on the screen. I've managed to get stderr and stdout into the file, but the expansions are only printed to the screen. Here is what I have so far:sudo -u <user> source my_job.sh |tee my_log.txt 2>&1
View 2 Replies View Related