I would like to put a variable in the $PS1 prompt that will change each time a command is run. I want the color of the $PS1 prompt to change each time a command is run.I know that I can do this:
Code:
PS1="h@w # "
## "#" is changes every time a command is run
[code]....
I want to display 4 options using the case command and refresh the screen when options 1 and 2 are chosen (no changes to the options and you get asked again to chose option), but give a message for option 3 and exit on option 4. I set this up with the script below, but choosing option 1 works and choosing option 2 exits the script.
Code:
#!/bin/bash
#testing options
Option="0"
[code]....
In my script, I need to get execution time of a command (say 'ls') in mili seconds level. For this i tried using "time" command to retrieve the total execution time in milli seconds. But, the problem is that, how to save the output of time command in a variable. The format of the command is like "time ls -R /opt" Going further, the o/p of 'time' command is:
real 0m0.003s
user 0m0.004s
sys 0m0.000s
Here, in my script, I would like to use only middle line "user 0m0.004s" saved to the variable but unable to find out the way.
I was reading that if I want to do a one time scheduled command, I should use at, which I've never done, as opposed to cron, which i'm kinda familiar with. But what I want to do is reboot my server at 3am tomorrow and force it to check the file systems with a shutdown -rF. For this do I even need to use "at" or could I just say shutdown -rF 3:00.Will that also know that I mean 3am tomorrow and not say in 3 minutes from now or 3pm?
View 14 Replies View Relatedwhile doing FTP through command prompt, connections times out after some time remaining idle, but doing ftp through browser, connection doesn't time out after some time remaining idle... why is it so?
View 2 Replies View Relatedsuppose i store the history number of a command say :
1004 cat file
Then now i want to run it like : !1004 but by using a variable.
command=1004
!$command
i am getting errors like :
command=1004command
I want pass a variable at compile time.
for example in x.c
int global_var = POSITION;
How can I send this POSITION at compile time. ie like # make POSITION=10 Is it possible?
I have an assignment that I have to change the prompt of shell through C.
View 11 Replies View Relatedi'm trying to execute a shell script, i'm trying to use the values in an array for use in a sed command:
sed -n '/Sales ID: ${array[$i]}/,/Totals:/p'
that command creates empty files. so my guess is that its not recognizing the array as an array but as text?
how would i be able to utilize the array in the command? i got it, didnt think that if i doubled up the single quotes that it would work, but this worked:
sed -n '/Sales ID: '${array[$i]'}/,/Totals:/p'
I am about to move my scripts to the next generation level, so I need some help I am stuck in varying my variable names in a loop. For example:
for user in ben dorothy mike pat
do
[ -r /home/$user ] && let "$user"check=1 || let "$user"check=0
[code]...
How to change string variable in awk? for example, I parse with awk script text file named some_name_with_extension.txt
I want to print only some_name in my script
Code:
....
varCompName = FILENAME
print varCompName
How to put not all symbols from FILENAME to variable?
[Code].....
Code:
ls Again the command can be stored in a variable and then executed. Like
Code:
var=ls
&var
The above two codes are the same. The problem occurs when we try to pipeline it. Consider the following problem:
Code:
ls | grep *
works fine...but when we try to store it in a variable and run the command there is an error.
Code:
var="ls|grep *"
$var
how to store this kind of commands in a variable?
I want to send a message from IP to Another IP through command prompt. how can i do this.s
View 3 Replies View RelatedI have the following code :
Code:
E_BADARGS=65
if [ $# -ne 2 ] ; then
[code]...
I am trying to create a server on my laptop. I have a windows 7 OS. I have downloaded Apache HTTP Server, MySQL Server and PHP. My Apache seems to be working well at one point i.e., when I use the http://localhost "It Works" does show in the browser. When I attempt to sign on the MySQL Server with my password the command prompt shuts off so quick I can't even read what the window says. The MySQL server seems to be running in the task manager under mysqld.exe.
End goal: have mysql running and adn communicating with php on apache.
I am having all sorts of trouble trying to assign a variable within an awk script with the system command. I know there is a lot of ways around this problem, but for efficiency reasons, I would like to, within my awk script, do something like
system(x=3)
or
system(x=NR)
and, latter on the shell script which calls the awk script, use the variable $x. But nothing is passed to x. I have already tried things like
command = "x=3"
system(command)
and also used a pipeline within the system to pipe it to /bin/sh In fact tried a lot of stuff like that, using $(( )) etc etc etc I can create directories e write to files (yes, i could write to a file and read from there, but I dont think it is efficient, plus I am puzzled).
Suppose I want to account number of files beginning with abc , I can use "ls 'abc* | grep abc | wc -l", this will return me a number.
I want to store this number in a variable, say var1, so I tried
1. "ls 'abc* | grep abc | wc -l |read var1", but this didn't work as var1 has no value somehow.
2. var1='ls 'abc* | grep abc | wc -l', this just assign the entire string "ls 'abc* | grep abc | wc -l" to var1, which is not I wanted.
I don't want to store the value to a temporary file and then read the value from that file. I think there should be a direct way to get the value, but don't know how. I know in tcsh, one can just use set var1='ls 'abc* | grep abc | wc -l', but it also doesn't work in bash. Can anyone give any clue about this?
I'm trying to create a program that would locate the oldest file of a certain type on a server. Here's the commands:
OLDEST_PATH=`find -L / -depth -maxdepth 6 -mindepth 6 -type d | sort -f | head -1`
OLDEST_FILE=`find -L $OLDEST_PATH | grep .mp3 | sort -f | head -1`
ls -al $OLDEST_FILE
I'm writing this all in expect but I'm having problems. The main problem I have is whenever I try to run the first command, I can't seem to isolate the result of the OLDEST_PATH so that the 2nd command will work. There always seems to be a newline in the variable and the result is only "find -L" command running and it bypasses the variable. If I can just figure out how to get the 1st and 2nd command to work, then I can figure out the 3rd. Here's some code:
Code:
send "find -L / -depth -maxdepth 6 -mindepth 6 -type d | sort -f | head -1
"
sleep 20
expect -re "(.*)
[Code]....
I know there is a better way to write this. I've tried multiple ways and this just happens to be the last way I've tried it. If you try running this, you'll notice that there is still carriage returns after the result of OLDEST_PATH and it prevents the 2nd "find" command from working properly.
Was trying to write a shell script that has if conditional statements to decide different arguments for a command.Basically:
Code:
if [ "$1" = 1 ]
then
[code]...
I have the following TCL code:
if{ [catch {sqlite3 db /path/to/db/file} result] } {
puts stderr $result
} else {
do something
}
What I want is to use a variable for the file name/path. When I put in a variable instead of the absolute path, I get an error: "missing close-brace: possible unbalanced brace in comment while executing"
This is weird because when I run the code with the fully qualified pathname, it works fine. I substitute out the pathname for a variable containing the pathname ($variable) and I get this error.
I'm trying to execute the following command within a bash script:
Code:
tac /var/log/system.log | head -1
The script I wrote is:
[code]...
I decided to install Chromium OS to my dad's netbook, and it works perfectly. The only problem is that i can't change the time. Luckily, I can access a command line by pressing CTRL+ALT+T. So maybe I can change it from the command line.
View 5 Replies View RelatedI'm running Red Hat Linux 5.4 on HP DL580 server with 16 processors and 64 GB of RAM. I'm connecting to the server remotely through SSH. after entering the password, it takes time to return the command line, if I click ctrl+c during this time, I'll have the command line prompt but not the correct bash prompt (I have to run bash to pass to my correct prompt).I tried to install Apache on the server, ./configure took 4 hours to finish instead of 1 or two minutes, Oracle installation same behavior. Server Disks are mirrored using RAID controller.
View 6 Replies View RelatedI have a question about the prompt. it is very easy to tune it for it to be colored and display path where you are etc. But my problem is that when the path is too long I would prefer the code line to be on the folowing line...
Ex
11:00 me@host a/short/path > ls -ltr ./stuff
11:00 me@host a/very/very/very/long/path
> ls -ltr ./stuff
and to be honnest as I am very new in LINUX I don't know how to do this...
I'm trying to read content of file to variable and use this variable in for loop. The problem is, when I have c++ comment style in file - /*. Spaces in line are also interpreted as separated lines.
For example:
Code:
Changing $files to "$files" eliminate these problems but causes that whole content of variable is treated as one string (one execution of loop).
my script has a variable which comes in the form +00.00 +0.00 -00.00 or -0.00 (the numbers can be any in that form) for any that have a + symbol I need to remove the +, but if it has a - symbol it needs to stay.
i need to make a new variable with the string from the old variable btut without any plus sign. I have tried a lot of different ways with no success, each thing I tried either left the + or removed the entire string. I think this should work but doesn't
foo=+12.40
bar=${foo#+}
how I can search within a variable and assign the results to a new variable. I'll use the following as an example -
cars="Audi BMW Cadillac Chevy Dodge Ferrari Ford Mercedes"
list=`echo ${cars} | egrep -o '<A?+|<C+'`
with the echo command I get the following output assigned to list -
A
C
C
What I'd like to get for output is -
Audi
Cadillac
Chevy
how I could do this regardless of upper/lower case letters?
included shell script inside c program, and i wanted to assign the value of c variable to shell variable..Can any one please suggest me how to do it?
View 8 Replies View RelatedThis loop is part of a bash script which takes multiple arguments.
Code:
for ((i=1;i<=$number;++i)) ; do
offset=$(($i+5))
[code]...
I found a way to change the kernel time zone with the following command
$ ln -sf /usr/share/zoneinfo/* /etc/localtime
After I tried it and checked the kernel time zone, but it didn't changed.
It seemed to be applied after rebooting.
Is there any way to change the kernel time zone "dynamically" with the
console command, not with the GUI environment?