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Windows/Linux child process STDIN differences

linux,windows,perl,process,stdin

This isn't a Windows verus Linux thing. You simply picked two awful examples. type con reads from the console, not from STDIN. This can be seen using type con <nul. cat is extremely unusual. Buffering, on either system, is completely up to the individual application, but almost all applications work...

Linux-wget command

linux,shell,wget

Try this to create a string variable n, with no leading whitespace (thanks @011c): n="10.0.0.135.527" wget http://infamvn:8081/nexus/content/groups/LDM_REPO_LIN64/com/infa/com.infa.products.ldm.ingestion.server.scala/"$n"-SNAPSHOT/com.infa.products.ldm.ingestion.server.scala-"$n"-20150622.210643-1-sources.jar ...

How to append entry the end of a multi-line entry using any of stream editors like sed or awk

linux,bash,awk,sed,sh

Here's a sed version: /^Host_Alias/{ # whenever we match Host_Alias at line start : /\\$/{N;b} # if backslash, append next line and repeat s/$/,host25/ # add the new host to end of line } If you need to add your new host to just one of the host aliases, adjust...

BASH - conditional sum of columns and rows in csv file

linux,bash,csv,awk

This awk program will print the modified header and modify the output to contain the sums and their division: awk 'BEGIN {FS=OFS=";"} (NR==1) {$10="results/time"; print $0} (NR>1 && NF) {sum8[$10]+=$8; sum9[$10]+=$9; other[$10]=$0} END {for (i in sum8) {$0=other[i]; $8=sum8[i]; $9=sum9[i]; $10=(sum9[i]?sum8[i]/sum9[i]:"NaN"); print}}' which gives: Date;dbms;type;description;W;D;S;results;time;results/time Mon Jun 15 14:22:20 CEST...

Get system startup time (without reading /proc/uptime)

php,linux

You don't need the -s flag to determine the uptime. If you do something like this you have the time the server is running: $tmp = explode(' ', exec('uptime')); $uptime = $tmp[2]; // something like 2:14 (hh:mm) nb: an alternative would be to use the who -b command, which will...

Using an ad-hoc libc with a tool which is an argument of another tool

linux,shared-libraries

You can achieve that by using the env utility: timeout 10 /usr/bin/env LD_LIBRARY_PATH=/path/to/mod/libc/ cp a b Env will set the environment variable and exec the other utility with that environment....

sed string with special character New

linux,sed,special-characters

Escape / with \: sed -i 's/mrm.fr.mycompany.com/10.70.89.40:8081\/artifactory/' config.xml Or use this: sed -i 's|mrm.fr.mycompany.com|10.70.89.40:8081/artifactory|' config.xml ...

Continuous data stream from linux command line into python script

python,linux,command-line,tcp,pipe

Would pipes and stdin work? Here is a similar question just asked a couple minutes ago. Reading from linux command line with Python...

Finding the average of a column excluding certain rows using AWK

linux,bash,awk,scripting

Through awk, $ awk '$5!="99999"{sum+=$5}END{print sum}' file 227.5 Explanation: $5!="99999" if 5th column does not contain 99999, then do {sum+=$5} adding the value of 5th column to the variable sum. Likewise it keeps adding the value of 5th column when awk see's the record which satisfies the given condition. Finally...

Nginx block access to referring url

linux,nginx,dns

It seems you need to add a catch-all server block: server { listen 80 default_server; server_name ""; return 444; } The 444 status code will close the connection without sending a response....

Bash script for basic mathematic operations

linux,bash,math

This reads each number from the input file, and outputs the correctly modified output to each output file. while IFS='' read -r number; do printf "%d\n" $((number + 5)) >&3 printf "%d\n" $((number * 5)) >&4 done < input.txt 3> first.txt 4> second.txt ...

How to check which symbols on my shared library have non-position independent code (PIC)?

linux,gcc,debian,powerpc

To find which symbols made your elf non-PIC/PIE (Position Independent Code/Executable), use scanelf from pax-utils package (on ubuntu, install it with sudo apt-get install pax-utils): $ scanelf -qT /usr/local/lib/libluajit-5.1.so.2.1.0 | head -n 3 libluajit-5.1.so.2.1.0: buf_grow [0x7694] in (optimized out: previous lj_BC_MODVN) [0x7600] libluajit-5.1.so.2.1.0: buf_grow [0x769C] in (optimized out: previous lj_BC_MODVN)...

Set label on group multiplot in gnuplot

linux,graph,plot,gnuplot

Instead of using xlabel and ylabel, you may want to go with set label. For example, #!/usr/local/bin/gnuplot datafile='tmp.dat' # file to plot set xlabel " " # no x-label set ylabel " " # no y-label # assuming all plots have same x and y range set xrange [-2:2] set...

Linux: Using split on limited space

linux,bash,file-io

My attempt: #! /bin/bash if [ $# -gt 2 -o $# -lt 1 -o ! -f "$1" ]; then echo "Usage: ${0##*/} <filename> [<split size in M>]" >&2 exit 1 fi bsize=${2:-100} bucket=$( echo $bsize '* 1024 * 1024' | bc ) size=$( stat -c '%s' "$1" ) chunks=$( echo...

awk error: each rule must have a pattern or an action part

linux,gawk

The errors, as awk helpfully (though verbosely) tells you awk: cmd. line:1: /^e/ {i++; rx[i]=$2}; tx[i]=$10}; END{printf(" down: %.2f Mbps, up: %.2f Mbps", ((rx[2]-rx[1])/1024/1024)), ((tx[2]-tx[1])/1024/1024))} awk: cmd. line:1: ^ syntax error awk: cmd. line:1: each rule must have a pattern or an action part awk: cmd. line:1: /^e/ {i++; rx[i]=$2};...

Check string index exist

linux,bash

#!/bin/bash declare -A SArray SArray[a]="a" SArray[b]="b" read index if test "${SArray["$index"]+isset}"; then echo "index $index exists for SArray" else echo "no index $index for SArray" fi ...

What does it indicate if /proc/PID/maps shows zero for all addresses?

linux,linux-kernel

I found the discussion in Valgrind mail list when someone had the same problem. The issue was that the kernel have been patched with PaX patches, one of which doesn't allow to look at the /proc/pid/maps. The quote about the patch from wikipedia The second and third classes of attacks...

Using indirect variable references in a Bash script

linux,bash

It seems like you're looking for an indirect variable reference. Your $cmd variable points to the variable $Apr and you want to use the value of $Apr. Here's how you can do this (just the relevant lines): cmd=$(date | awk '{print $2}') eval month=\$$cmd dat=$(ls -ltr | grep $month |...

Ignore first few lines and last few lines in a file Linux

linux,awk

awk cannot look ahead so you'll have to save the lines. awk 'NR>2{if(z!="")print z;z=y;y=x;x=$0}' file Practically zero memory overhead...

PHP `require_once` includes wrong file

php,linux,ext4

Have you checked any potential opcode caches and their settings? In the past I have had some issues there, eg not detecting changed files. Specifically, this situation can and will happen if opcache.use_cwd setting is set to zero. opcache.use_cwd boolean If enabled, OPcache appends the current working directory to the...

The range of virtual memory address in userspace

c,linux,memory

The possible range of virtual addresses is processor and kernel and ABI specific. But I strongly advise against coding some tricks related to some bits in addresses and pointers (since your code might work on some processors, but not on others). These days, some * x86-64 processors apparently use only...

AWK count number of times a term appear with respect to other columns

linux,shell,command-line,awk,sed

Almost same as the other answer, but printing 0 instead of blank. AMD$ awk -F, 'NR>1{a[$2]+=$3;b[$2]++} END{for(i in a)print i, a[i], b[i]}' File pear 1 1 apple 2 3 orange 0 1 peach 0 1 Taking , as field seperator. For all lines except the first, update array a. i.e...

error using already compiled version of openCV

c++,c,linux,opencv

You have not linked the executable against several libraries that are required by the program Try using this: g++ -lpthread `pkg-config opencv --libs` -I/usr/local/include/ -lraspicam -lraspicam_cv -L/opt/vc/lib -lmmal -lmmal_core -lmmal_util -I/usr/include -lwiringPi test3.cpp -o test3 ...

Linux : pthread_cond_signal() is not working inside a Signal Handler()

c++,c,linux,signals,posix

In Signal handler there are only a very limited number of syscalls allowed. see man 7 signal http://man7.org/linux/man-pages/man7/signal.7.html My Suggestion is, to be on the safe side, the so called "self pipe trick". http://man7.org/tlpi/code/online/diff/altio/self_pipe.c.html You could start a thread which runs a select Loop on the self pipe and call...

fread(), solaris to unix portability and use of uninitialised values

c,linux,memory,stack,portability

Q 1. why is ch empty even after fread() assignment? (Most probably) because fread() failed. See the detailed answer below. Q 2.Is this a portability issue between Solaris and Linux? No, there is a possible issue with your code itself, which is correctly reported by valgrind. I cannot quite...

Am I using z3 :timeout correctly with C++ interface for Linux?

c++,linux,z3

Timeout through the API is definitely supported. Maybe 100ms on your Linux box is too much? Can you try with a smaller timeout? If it still fails, could you file a bug report with a short, self-contained, reproducing test case? Thanks!...

Haskell make recipe fails for Paradox theorem prover using GHC

linux,haskell,make,ghc,theorem-proving

Looks like paradox was written for a rather old version of GHC. You can fix all these "Could not find module" errors by using GHC version 7.8 or older and setting GHC = ghc -hide-package base -package haskell98 in the Makefile, though you will likely encounter more errors after that....

Bash modify CSV to change a field

linux,bash,awk

Please save following awk script as awk.src: function date_str(val) { Y = substr(val,0,4); M = substr(val,5,2); D = substr(val,7,2); date = sprintf("%s-%s-%s",Y,M,D); return date; } function time_str(val) { h = substr(val,9,2); m = substr(val,11,2); s = substr(val,13,2); time = sprintf("%s:%s:%s",h,m,s); return time; } BEGIN { FS="|" } # ## MAIN...

ret_from_syscall source code and when it is called

linux,linux-kernel,kernel,linux-device-driver,system-calls

The ret_from_syscall symbol will be in architecture-specific assembly code (it does not exist for all architectures). I would look in arch/XXX/kernel/entry.S. It's not actually a function. It is part of the assembly code that handles the transition from user-space into kernel-space for a system call. It's simply a label to...

Linux/shell - Remove all (sub)subfolders from a directory except one

linux,delete,find,folder,rm

Using PaddyD answer you can first clean unwanted directories and then delete them: find . -type f -not -path "./gallery/*/full/*" -exec rm {} + && find . -type d -empty -delete ...

How To Restore a Missing Redis Service

linux,redis,centos

Do you want to remove redis old package you can use yum remove command as below. yum remove redis then check it still available as below rpm -qi redis and also check files rpm -ql redis if its there you can remove as below. rpm -e redis (or you can...

Java read bytes from Socket on Linux

linux,windows,sockets,network-programming,raspberry-pi

InputStream input = client.getInputStream(); BufferedReader in = new BufferedReader(new InputStreamReader(input)); Your problem is here. You can't use multiple inputs on a socket when one or more of them is buffered. The buffered input stream/reader will read-ahead and 'steal' data from the other stream. You need to change your protocol so...

How to remove characters before and including an underscore?

linux,string,bash,unix,awk

Using Parameter Expansion: $ var="fooo_barrrr" $ echo ${var#*_} barrrr To change the var itself, var=${var#*_}. Note this removes up to the first _: $ var="fooo_barrr_r" $ echo ${var#*_} barrr_r If you wanted to remove up to the last one, you would need to use ## instead: $ var="fooo_barrr_r" $ echo...

Force linux to use php as php55

php,linux,fedora

You can create an alias: alias php="php55" Now if you type php it uses php55...

Django MySQLClient pip compile failure on Linux

python,linux,django,gcc,pip

It looks like you're missing zlib; you'll want to install it: apt-get install zlib1g-dev I also suggest reading over the README and confirming you have all other dependencies met: https://github.com/dccmx/mysqldb/blob/master/README Also, I suggest using mysqlclient over MySQLdb as its a fork of MySQLdb and what Django recommends....

How can I resolve the “Could not fix timestamps in …” “…Error: The requested feature is not implemented.”

linux,build,f#

This is usually a sign that you should update your mono. Older mono versions have issues with their unzip implementation

How to schedule an R Script Cronjob in a linux server? [closed]

linux,r,cron,crontab

The following cron job will run Rscript scriptSecos.R from the path /home/script2, once a day, at 0:00 (midnight). 0 0 * * * cd /home/script2; Rscript scriptSecos.R >/dev/null 2>&1 If you want to save the output of the script to a file, change >/dev/null with >/path/to/file. You can copy and...

count the values based on condition in log

linux,shell

try this: cat path_to_your_log_file|awk '{split($2,res,":");var=res[1]":"res[2]":"res[3];counter[var]+=$1}END{for(i in counter){print counter[i],i}}' ...

While loop in bash using variable from txt file

linux,bash,rhel

As indicated in the comments, you need to provide "something" to your while loop. The while construct is written in a way that will execute with a condition; if a file is given, it will proceed until the read exhausts. #!/bin/bash file=Sheetone.txt while IFS= read -r line do echo sh...

What are correct permissions for Linux Apache2 PHP 5.3 log file?

php,linux,apache,logging,permissions

I'd simply set its owner to apache user. This will give you the name of apache user : ps aux | grep httpd In my case (CentOS), it's 'apache' but sometimes it's 'www-data'... chown apache:apache /var/log/httpd/php_errors.log chmod 600 /var/log/httpd/php_errors.log ...

debian 8: deb command not found. How can i fix it? [closed]

linux,debian,deb

The instruction is Add "contrib" and "non-free" components to /etc/apt/sources.list, for example I.e., you're supposed to add that line to the given file with a text editor. You are not supposed to execute it on a command line....

How could I simulate a lack of file descriptor?

c,linux,file-descriptor

You can limit the number of file descriptors a process can open under Linux using ulimit. Executing ulimit -n 3 before running your C program should make it an error to open any more files, since stdin, stdout, and stderr take up the first 3 descriptors. An example: $ ulimit...

Are the C functions recvfrom and sendto mutually exclusive?

c,linux,sockets,udp,thread-safety

Are the C functions recvfrom and sendto mutually exclusive? No. They can both be executed by different threads at the same time. sendto() doesn't wait for recvfrom() to read the data. It would place the data into the socket's buffer and return. Multiple sendto() may block for the previous...

Applying chmod 755 (or other) when ftping to apache var/www/ virtual host directories?

linux,apache,chmod

I think what you are looking for is umask umask 0022 umask -p umask -S You will need to modify your default /etc/profile in order to make this permanent. umask 0022will on creation give directories chmod 755 and files chmod 644 which is the recommended permissions for the www folder...

how to compare only date from a model's datetimefield with current date?

python,linux,django,web,frameworks

You can use the __range field lookup: start = datetime.date.today() end = start + datetime.timedelta(days=1) Model.objects.filter(datetime__range=(start, end)) ...

ERROR 1130 (HY000) or ERROR 2003 (HY000) : connect mysql from windows to ubuntu on VMware

mysql,linux

1) change my.conf (whatever your mysql conf file is called). And set bind-address to 0.0.0.0 as it is prob 127.0.0.1 2) stop/restart mysql daemon Connections now are not limited to those from localhost. The default is localhost for obvious security reason until dev guy tweaks it 3) grants with flush...

How to extract first letters of dashed separated words in a bash variable?

linux,string,bash,shell,variables

This isn't the shortest method, but it doesn't require any external processes. IFS=- read -a words <<< $MY_TEXT for word in "${words[@]}"; do MY_INITIALS+=${word:0:1}; done ...

Python Thread Breaking Terminal

python,linux

It seems the process you control is changing terminal settings. These are bypassing stderr and stdout - for good reasons. E.g. ssh itself needs this to ask users for passwords even when it's output is being redirected. A way to solve this could be to use the python-module pexpect (it's...

NASM: copying a pointer from a register to a buffer in .data

linux,assembly,nasm,x86-64

The problem is, you don't have debug info for the ptr type, so gdb treats it as integer. You can examine its real contents using: (gdb) x/a &ptr 0x600124 <ptr>: 0x7fffffffe950 (gdb) p/a $rsp $3 = 0x7fffffffe950 Of course I have a different value for rsp than you, but you...

What is the difference between `./example.sh` and `sh example.sh`

linux,bash,shell

array_name=(value1 ... valuen) This is how to initializes an array in bash only. When you execute ./example.sh, the shebang line #!/bin/bash tells the system to use bash to execute. However, when you execute sh example.sh, sh is used to execute. In many Unix systems (like Linux), sh is equivalent to...

why is u8 u16 u32 u64 used instead of unsigned int in kernel programming

c,linux,kernel,linux-device-driver

Often when working close to the hardware or when trying to control the size/format of a data structure you need to have precise control of the size of your integers. As for u8 vs uint8_t, this is simply because Linux predated <stdint.h> being available in C, which is technically a...

C: Linux to Windows: Sending text file over TCP produces not exact copy on the Windows side

c,linux,windows,sockets,tcp

When sending, you're assuming the data is null terminated: if((send(sockfd, buf, strlen(buf), 0)) < 0){ You should use the count actually returned by the read method, and you shouldn't use fgets() for that purpose. Your receive loop makes no sense. You're calling recv() several times and testing the result...

Change a Script to a For Do Done Loop

linux,bash,for-loop,awk

Turns out the code wasn't invalid (had to correct some quoting issues) but that the folder was corrupt when i tried to use it in the bash script. Here is the working code with the correct double quotes around the directory variables. #!/bin/bash #file location XMLDIR='/home/amoore19/XML/00581-001/scores' NEWXML='/home/amoore19/XML/00581-001' #this gives me...

Shell script to loop over files with same names but different extensions

linux,bash,shell

anubhava's solution is excellent if, as they do in your example, the extensions sort into the right order. For the more general case, where sorting cannot be relied upon, we can specify the argument order explicitly: for f in *.ext1 do program "$f" "${f%.ext1}.ext2" done This will work even if...

Slimerjs with exec linux centos 6

php,linux,exec,slimerjs

Had same issue now, just a minute ago. But I am using a combination of Casperjs with Slimerjs engine (Casperjs is a great tool for working with your slimerjs and phantomjs scripts, in a friendlier enviroment programming). The working php script: <?php putenv("PHANTOMJS_EXECUTABLE=/usr/local/bin/phantomjs"); putenv("CASPERJS_EXECUTABLE=/usr/local/bin/casperjs"); putenv("SLIMERJS_EXECUTABLE=/usr/local/bin/slimerjs"); putenv("DYLD_LIBRARY_PATH"); echo passthru('/usr/bin/xvfb-run /usr/local/bin/casperjs --ssl-protocol=any...

How to look at the top 30 lines (or head) of all files inside a directory?

linux

You can use globbing: head -n 10 *.cpp > all_headers.txt The above command exports the first 10 lines of all cpp files in a folder into all_headers.txt. According to Aereaux's comment you should also use the -q option of head since otherwise head would print the file name before the...

Syncing Vagrant VMs across different physical servers

linux,vagrant,backup,virtual-machine,sync

Vagrant doesn't inherently support this, since it's intended audience is really development environments. It seems like you're looking for something more like what VMWare vSphere does.

Is it possible to run command “route -n” specifically for a NIC

linux,shell,scripting

Do you want see route for ether0, you can use below command ip -o route show dev ether0 or ip route show | grep ether0 or route -n | grep ether0 or netstat -nr | grep ether0 To see NIC for ether0, you can use ifconfig command and Gateway NIC...

launch several scripts located in subdirectories

linux,bash,shell

Try doing it using find and for: for file in `find . -type f -name "*.sh"`; do sh $file; done Use can also store it in array and do it: array=($(find . -type f -name "*.sh")) for file in ${array[@]};do sh $file; done ...

Calling find more than once on the same folder tree

linux,bash,shell,unix,find

Try this: find . -mmin +35 -or -mmin -25 find supports several logical operators (-and, -or, -not). See the OPERATORS section of the man pages for more details. ==================== EDIT: In response to the question about processing the two matches differently, I do not know of a way to do...

Recursively copy /dev/null to file pattern

linux,command-line,zfs

find $DELDIR -type f | xargs cp /dev/null where $DELDIR is the name of the directory to start in. The -type f option targets only files, not directories. And of course xargs just finishes off cp /dev/null with the file names from each line of find output....

Two part: How to run 'ls' from a java program and how to tell computers on a storm cluster to execute specific commands

java,linux,storm,topology

You can use below snippet to run a command in shell. So use this same method to invoke the specific ls command using ssh in all supervisor nodes (from external node like nimbus). public String executeCommand(String command) { StringBuffer output = new StringBuffer(); Process p; try { p = Runtime.getRuntime().exec(command);...

Git post-receive hook is not executed

linux,git,githooks,git-post-receive

The hook file is incorrectly named post-reveive.

Debugin UDI program by gdb

linux,gdb

Change the order of your struct like this struct user_info { char name[16]; uid_t uid; }; It will override as your expect....

Extra backslash when storing grep in a value

linux,bash

The output from set -x uses single quotes. So the outer double quotes were replaced with single quotes but you can't escape single quotes inside a single quoted string so when it then replaced the inner double quotes it needed, instead, to replace them with '\'' which ends the single...

make error during building webkitgtk

linux,makefile,cmake,make

as you see, in Edit1, you (make) try to run JavaScriptCore-4.0.gir instead of compile it with g-ir-compiler; I tried on my pc and my command is: cd /home/davide/src/webkitgtk-2.8.3/build/Source/JavaScriptCore && \ /usr/bin/g-ir-compiler /home/davide/src/webkitgtk-2.8.3/build/JavaScriptCore-4.0.gir \ -o /home/davide/src/webkitgtk-2.8.3/build/JavaScriptCore-4.0.typelib as a workaround, you cand edit: build/Source/JavaScriptCore/CMakeFiles/JavascriptCore-4-gir.dir/build here's the lines on my file (the last...

AH01630: client denied by server configuration Apache

linux,apache,.htaccess,prestashop,prestashop-1.6

There are a couple of things I see just looking at the configuration. You have your vhost config named etc/apache2/sites-enabled/prestashop.config But that is not the file type that is being included in the apache.conf file. # Include the virtual host configurations: IncludeOptional sites-enabled/*.conf Your apache setup looks for .conf files...

Group of data in shell language

linux,bash,shell

In x="1 2 3" for i in $x what you are doing is for i in 1 2 3:. But in second case doing xm=`cat $x` ym=`cat $y` This might lead to error saying No such file or directory is the echo $x and echo $y file does not exit....

sed and PHP tags

regex,linux,sed

.* is greedy: it matches all possible characters. This way, even sed 's/<?php.*//' file will also delete all the content in your file. To prevent this greediness of .*, say "everything but a ?" -> [^?]*: sed 's/<?php[^?]*?><?php[^?]*?>//' file Test $ cat a <?php echo 'first' ?><?php echo 'second' ?><?php...

How to do the expansion of variable in shell script? [duplicate]

linux,bash,shell,unix,ksh

Using bash -c: newvar="$(bash -c "echo $var")" Using eval: newvar="$(eval "echo $var")" Example: #!/bin/bash var='$PATH' echo "$var" #This will show that $var contains the string $PATH literally #Using bash -c newvar="$(bash -c "echo "$var"")" echo "$newvar" #using eval newvar="$(eval "echo "$var"")" echo "$newvar" It will print the environment variable paths...

Reading from linux command line with Python

python,linux,shell,command-line

You need to read stdin from the python script. import sys data = sys.stdin.read() print 'Data from stdin -', data Sample run - $ date | python test.py Data from stdin - Wed Jun 17 11:59:43 PDT 2015 ...

Delete some lines from text using Linux command

linux,shell,sed,grep,pattern-matching

The -v option to grep inverts the search, reporting only the lines that don't match the pattern. Since you know how to use grep to find the lines to be deleted, using grep -v and the same pattern will give you all the lines to be kept. You can write...

Problems with filename encoding on Linux when created through Java

java,linux,encoding

Well, it appears this is a long standing bug in the older File API. I've solved all my problems - with no additional configs of any kind - by switching to the newer java.nio package.

How to replace newlines/linebreaks with a single space, but only if they are inside of start/end regexes?

regex,linux,shell,unix,replace

You can do it using awk as: awk '/\[x/{f=1} {if(f)printf "%s",$0; else print $0;} /y\]/{print ""; f=0}' Output: [x data1 data2 data3 data4 y] [a data5 data 6 data7 data 8 b> [x data y] You can also simplify to: awk '/\[x/,/y\]/{ORS=""; if(/y\]/) ORS="\n";}{print}' Output: [x data1 data2 data3 data4...

Linux - sh script - download multiple files from FTP

linux,ftp,sh

wget expect can be tricky to work with so I'd prefer to use GNU Wget as an alternative. The following should work as long as you don’t have any spaces in any of the arguments. for v in "${files_to_download[@]}" do ftp_file="${v}.bz2" wget --user=${USER} --password=${PASSWD} ${HOST}/${ftp_file} done Request multiple resources using...

shell script to shutdown/restart Linux system

linux,shell

Yes, use the -S switch which reads the password from STDIN: $echo <password> | sudo -S <command> Exposing your password is generally bad idea search for something that can protect / hide it. In the past I've used Jenkins plugins to do this while executing the scripts regularly....

cat /dev/null to multiple files to clear existing files like logs

linux,bash,shell,command-line,tee

Hard coded solutions tee Echo nothing and simple send it to multiple files using the tee command. Like this: $ echo -n | tee file1 file2 file3 file4 file5 All files in that list will be empty and created if they don't exist. Applied to your answer this would be:...

How to find average and maximum in an interval using Shell [closed]

linux,bash,shell,unix,awk

Please make a search before you ask any question many posts are already there You can try something like below, modify accordingly Input [[email protected] tmp]$ cat input.txt 1 3 2 5 3 4 4 3 5 2 6 1 7 3 8 3 9 4 10 2 11 2 12...

Error while executing lsof from bash script

linux,bash,shell,scripting

You have additional spaces at the declaration of IS_RUNNING. Try IS_RUNNING="$(lsof...)" ...

Unable to connect to mysql after automating mysql-server installation in bash script

mysql,linux,bash,unix

I think Álvaro its right about the quotes, try something like debconf-set-selections <<< "mysql-server mysql-server/root_password password $passdb" debconf-set-selections <<< "mysql-server mysql-server/root_password_again password $passdb" ...

How does the kernel separate threads from processes

linux,multithreading,linux-kernel

Unlike Windows, Linux does not have an implementation of "threads" in the kernel. The kernel gives us what are sometimes called "lightweight processes", which are a generalization of the concepts of "processes" and "threads", and can be used to implement either. It may be confusing when you read kernel code...

Spring batch FileItemWriter not creating file at correct path

java,linux,spring,websphere,spring-batch

You are using backslashes in the the value of fileLocation. They are valid file name characters in linux. You should change the path to /opt/temp/.

how to modify an array value with given index?

arrays,linux,bash

You don't need the quotes. Just use ${i}, or even $i: pomme[${i}]="" Or pomme[$i]="" ...

Redirect stdout using exec in subscript

linux,bash,redirect,command-line,sh

Solution based on the comment from "Zaboj Campula": if /bin/grep -q "^[[:space:]]/usr/bin/enigma2_pre_start.sh$" /var/bin/enigma2.sh then echo Unpatched > /tmp/enigma.sh /bin/sed -e 's/^\t\(\/usr\/bin\/enigma2_pre_start.sh\)$/\t\. \1/g' /var/bin/enigma2.sh -i pid=`/bin/ps -o ppid= $$` && /bin/kill $pid fi ...

how to spy on linux binaries for testing of shell scripts

linux,bash,shell,testing,spy

Just an idea, I didn't see this anywhere but: Unless you're using full paths to invoke those binaries, you could create mocks of those libraries, e.g., in your projects bin/ directory and make that directory be the first in your $PATH. export PATH="$PWD/bin:$PATH" To mock grep, for example, you could...

how to determine directory or file in linux in c

c,linux

What you are looking for is stat or one of its variants. Specifically look at the st_mode field of struct stat. The macro you are interested in is S_ISDIR(x). Find below your modified code that demonstrates what you want: void list_file(char* directory) { DIR *d; struct dirent *dir; int dir_len...

Extract minor version from kernel to bash variable

linux,bash,sed,cut

The problem is you are using -c to cut. Don't do that. Use the -f and -d flags instead to control the delimiter and fields to output. Or use awk -F . '{print $2}' <<< "$(uname -r)". Or use IFS=. read -r _ minor _rest <<< "$(uname -r)"; echo "$minor"...

AWK write to new column base on if else of other column

linux,bash,shell,awk,sed

You can use: awk -F, 'NR>1 {$0 = $0 FS (($4 >= 0.7) ? 1 : 0)} 1' test_file.csv ...

How to extract single-/multiline regex-matching items from an unpredictably formatted file and put each one in a single line into output file?

linux,shell,unix,replace,grep

Assuming that your document is well-formed, i.e. <b> opening tags always match with a </b> closing tag, then this may be what you need: sed '[email protected]<[/]\?b>@\n&\[email protected]' path/to/input.txt | awk 'BEGIN {buf=""} /<b>/ {Y=1; buf=""} /<\/b>/ {Y=0; print buf"</b>"} Y {buf = buf$0} ' | tr -s ' ' Output: <b>data1</b>...

linux running command as root from c code that run as normal user

c++,linux

A workaround is to modify the sudoers file and remove the requirement of a password from your user ID for a particular script to have sudo privileges. Enter sudo visudo After this, add the details in the following manner. username ALL=(ALL) NOPASSWD: /path/to/script Another method would be to pipe the...