In the following:
[09:15:22] /tools # pwd
/tools
[09:15:23] /tools # echo foo
foo
[09:15:27] /tools #
I want to read everything preceding the "#" (I'll call it the signature for now). The signature is auto-filled by the shell on every line where a user can input text.
I tried looking through uname without luck, and I've spent a good deal of time trying to find the proper name for this "signature" without success. Is there a way to do this (or, does anyone know the correct name for what I'm trying to read)?
Related
I'm trying to replace the word in shell script with sed -e command but its not replacing , please help on that, i have tried the below
we have separate file in /data/docs/config.log, in that file there is a word ?account for example ,
username acc, passsword acc, ?account.name
this ?account word needs to be replaced with word 'GLOBAL' using sed -e command ,
reacc = GLOBAL
sed -e "s/?account/$reacc/g" /data/docs/config.log > /data/docs/newconfig.log
but here the file newconfig.log has created with 0 size , no output written to the file , its not replacing its an empty file,
the output should be username acc, passsword acc, GLOBAL.name in newconfig.log
Being the only person who can reproduce the problem, you are pretty much on your own. There are plenty of things you can do to analyze the problem, though.
Double-check the shell. Don't have blind faith in #!/bin/sh. In cygwin for example, /bin/sh is an alias for bash. Verify with: echo $SHELL
Check permissions and file system. Do you have rights to write to the output file? Is the disk full? Does cat /data/docs/config.log > /data/docs/newconfig.log work? Test again in a different folder.
Double-check the output file. Is it really empty, or is the file system just slow with updating the file size? Is sed really finished? Test without output redirection; see if the output is dumped to stdout.
Test with a small file; one or two lines is enough.
If even that does not work, then test sed itself. Who knows, maybe you have a weird alias that hides the real sed. The most trivial filter is sed -e '', which should simply echo every line you type (just like cat without parameters). Does that work? Then try some simple patterns.
Systematically iterate between test cases that succeed and test case that fail, until you have found the breaking point. Doing so, you should be able to find the cause. Sorry, that's all I can do for you right now.
Remove spaces around =. Try after making
reacc=GLOBAL
I have a script in one of my application folders.Usually I just cd into that locatin in Unix box and run the script e.g.
UNIX> cd My\Folder\
My\Folder> MyScript
This prints the required result.
I am not sure how do I do this in Bash script.I have done the following
#!/bin/bash
mydir=My\Folder\
cd $mydir
echo $(pwd)
This basically puts me in the right folder to run the required script . But I am not sure how to run the script in the code?
If you can call MyScript (as opposed to ./MyScript), obviously the current directory (".") is part of your PATH. (Which, by the way, isn't a good idea.)
That means you can call MyScript in your script just like that:
#!/bin/bash
mydir=My/Folder/
cd $mydir
echo $(pwd)
MyScript
As I said, ./MyScript would be better (not as ambiguous). See Michael Wild's comment about directory separators.
Generally speaking, Bash considers everything that does not resolve to a builtin keyword (like if, while, do etc.) as a call to an executable or script (*) located somewhere in your PATH. It will check each directory in the PATH, in turn, for a so-named executable / script, and execute the first one it finds (which might or might not be the MyScript you are intending to run). That's why specifying that you mean the very MyScript in this directory (./) is the better choice.
(*): Unless, of course, there is a function of that name defined.
#!/bin/bash
mydir=My/Folder/
cd $mydir
echo $(pwd)
MyScript
I would rather put the name in quotes. This makes it easier to read and save against mistakes.
#!/bin/bash
mydir="My Folder"
cd "$mydir"
echo $(pwd)
./MyScript
Your nickname says it all ;-)
When a command is entered at the prompt that doesn't contain a /, Bash first checks whether it is a alias or a function. Then it checks whether it is a built-in command, and only then it starts searching on the PATH. This is a shell variable that contains a list of directories to search for commands. It appears that in your case . (i.e. the current directory) is in the PATH, which is generally considered to be a pretty bad idea.
If the command contains a /, no look-up in the PATH is performed. Instead an exact match is required. If starting with a / it is an absolute path, and the file must exist. Otherwise it is a relative path, and the file must exist relative to the current working directory.
So, you have two acceptable options:
Put your script in some directory that is on your PATH. Alternatively, add the directory containing the script to the PATH variable.
Use an absolute or relative path to invoke your script.
I was just put on a task to try and debug and figure out why our ec2-consistent-snapshot script isn't working.
Our lead programmer followed this blog post.
We have a .sh script that we'd like to take the snapshot and it looks like this:
#!/bin/sh
/opt/aws/bin/ec2-consistent-snapshot --aws-access-key-id MYACCESSKEY --aws-secret-access-key MYSECRETKEY --freeze-filesystem /vol --mysql --mysql-host localhost --mysql-socket /var/lib/mysql/mysql.sock --mysql-username USERNAME --mysql-password PASSWORD --description "Demo MySQL data volume: $(date +%c)" vol-MYVOL
If I run this by doing sudo ./snapshot_script.sh I get a single error:
ec2-consistent-snapshot: ERROR: create_snapshot: File does not exist: at /usr/share/perl5/vendor_perl/Net/Amazon/EC2.pm line 232
I of course followed this error and line 232 in EC2.pm is this:
my $ref = $xs->XMLin($xml);
I have 0 perl experience and I don't know what this could be doing.
Any help would be wonderful.
The Net::Amazon::EC2 that I'm looking at on CPAN has that line at 252, not 232 so perhaps you are not on the latest version. Looking above that line, the program has attempted to do a "query to sign" using lots of the security parms. I suspect there is a problem with the authentication keys you are using. There is a debug flag, you might want to turn that on to generate more messages.
If you go to this page, you will see that XMLin() is a function of XML::Simple, and it takes a file as an argument. So, $xml is presumably a variable that contains an xml file name. That file does not exist.
The next step would be to trace the error back into the source code of ec2-consistent-snapshot, in order to see how it is calling XML::Simple and where the bad value gets passed in.
It's the first time i try to generate a VCD and i am getting some troubles.
I have a testbench called bench_minimips.vhdl that contain the entity sim_minimips.
I want simulate it and get a VCD out of it.
i am typing the following command in the Modelsim shell:
vsim work.sim_minimips
vcd file myvcd1.vcd
vcd add -file bench_minimips.vhd/*
run
but if i open myvcd1.vcd in an empty file. What should i do to create the dump?
I tryed as well as sudgested in another forum the command:
wlf2vcd -o myvcd2.vcd vsim.wlf
but a error is generated.
I am really lost in understanding because all the websites i find tells you to use a TCL generated by altera or some other company and i do not have theyr content to look at.
Does someone knows what should i do?
Best,
Stefano
The -file parameter to vcd add is not used to specify signals but the name of the VCD (if you've created several).
What you want to do instead is to add objects in your simulation. For example:
vcd file myvcd1.vcd
vcd add -r /sim_minimips/*
I am trying to use diffstrings.py from Three20 on my iPhone project, and I can't find the proper format for the path arguments (as in "Usage: diffstrings.py [options] path1 path2 ...").
For example, when I run the script in my Xcode project directory like this
~/py/diffstrings.py -b
it analyzes just the main.m and finds 0 strings to localize,
then it diffs against existing fr.lproj and others, and finds that thes contain "obsolete strings".
Can anyone post examples of successful comand line invocations of diffstrings.py, for options -b, -d and -m?
Taking a quick look at the code here http://github.com/facebook/three20/blob/master/diffstrings.py I see that if you don't specify any command line options, it assumes you mean the directory wherever the script lives in. So the option is to either copy .py file to where your .m files are, or simple use the command
~py/diffstrings.py -b .
That is, give the current directory (.) as the path argument.