I have an geom_uzip image and what I'm confused about is the following. The first few lines of the image file are as follows:
#!/bin/sh
#V2.0 Format
m=geom_uzip
(kldstat -m $m 2>&-||kldload $m)>&-&&mount_cd9660 /dev/`mdconfig -af $0`.uzip $1
exit $?
But when I try to execute them manually they simply don't work on the mount part as the memory drive with extension .uzip doesn't exist. For example executing mdconfig -af root.img generates /dev/md0, but the the top of the image loads the file_name.uzip. How is that happening ?
Also, I've been looking around for ways of testing the geom_uzip images and can't really find anything online. Does anyone know of any?
Related
I made a shell script the purpose of which is to find files that don't contain a particular string, then display the first line that isn't empty or otherwise useless. My script works well in the console, but for some reason when I try to direct the output to a .txt file, it comes out empty.
Here's my script:
#!/bin/bash
# takes user input.
echo "Input substance:"
read substance
echo "Listing media without $substance:"
cd media
# finds names of files that don't feature the substance given, then puts them inside an array.
searchresult=($(grep -L "$substance" *))
# iterates the array and prints the first line of each - contains both the number and the medium name.
# however, some files start with "Microorganisms" and the actual number and name feature after several empty lines
# the script checks for that occurence - and prints the first line that doesnt match these criteria.
for i in "${searchresult[#]}"
do
grep -m 1 -v "Microorganisms\|^$" $i
done >> output.txt
I've tried moving the >>output.txt to right after the grep line inside the loop, tried switching >> to > and 2>&1, tried using tee. No go.
I'm honestly feeling utterly stuck as to what the issue could be. I'm sure there's something I'm missing, but I'm nowhere near good enough with this to notice. I would very much appreciate any help.
EDIT: Added files to better illustrate what I'm working with. Sample inputs I tried: Glucose, Yeast extract, Agar. Link to files [140kB] - the folder was unzipped beforehand.
The script was given full permissions to execute. I don't think the output is being rewritten because even if I don't iterate and just run a single line of the loop, the file is empty.
Background
I've a script. It's purpose is to generate config files for various system services from templates whenever my gateway acquires a new IP from my ISP. This process includes making successive edits with sed to replace $[template] strings in my custom templates with the correct information.
And to do that I've created a small function designed to take input from stdin, redirect it to a temporary file passed as an argument, and then move that file to replace the destination (and also, often, source) config file. The "edit-in-place dance", if you will.
I created a simple test script with the problematic function:
#!/bin/bash
inplace_dance() {
read -r -d '' data
printf '%s' "${data}" > "${1}~"
mv "${1}~" "${1}"
}
# ATTN: ls is only being used to generate input for testing. It is not being parsed.
ls -l ~/ | inplace_dance ~/test.out
Unfortunately, this works. So it's not the function itself. I also tried it with my custom logging utility (see "complications" below):
#!/bin/bash
. /usr/local/lib/logging.bash
log_identifier='test'
log_console='on'
inplace_dance() {
read -r -d '' data
printf '%s' "${data}" > "${1}~"
mv "${1}~" "${1}"
}
# ATTN: ls is only being used to generate input for testing. It is not being parsed.
bashlog 'notice' $(ls -l ~/ | inplace_dance '/home/wolferz/test.out')
This also works.
The Problem
In its original context, however, it does not work. I've confirmed that ${data} gets set just fine. And that ${1} contains the correct filename. What fails is the second line of the function. I've confirmed printf is being run (see, "Additional Info - Without The Redirect" below)... but the file its output is being redirected to is never created.
And I've been over the code a dozen-dozen times (not an exaggeration) and have yet to identify the cause. So, in desperation, I'm going to post it here and hope some kind soul will wade through my code and maybe spot the problem that I'm missing. I'd also happily take advice on improvements/replacements to my logging utility (in the hopes of tracking down the problem) or further troubleshooting steps.
Here is the original context. The important lines are 106-110, 136-140, 144-147, and 151-155
Additional Info
☛ PATH/Environment
The PATH is PATH=/usr/local/sbin:/usr/local/bin:/usr/bin. I believe this is being inherited from systemd (systemd=>dhcpcd.service=>dhcpcd=>dhcpcd-run-hooks=>dhcpcd.exit-hook).
dhcpcd-run-hooks (see "Complications" below) does clear the environment (keeping the above PATH) when it runs. Thus, I've added an example of the environment the script runs in to the "original context" gist. In this case, the environment when $reason == 'BOUND'. This is output by printenv | sort at the end of execution (and thus should show the final state of the environment).
NOTE: Be aware this is Arch Linux and the absence of /bin, /sbin, and /usr/sbin in the PATH is normal (they are just symlinks to /usr/bin anyway).
☛ Return Code
Inserting echo $? after the second line of the function gives me a return code of "0". This is true both with the redirect in line 2 and without (just the printf).
☛ Without The Redirect
Without the redirect, in the original context, the second line of the function prints the contents of ${data} to stdout (which is then captured by bashlog()) exactly as expected.
⚠️ Execute Instead of Source.
Turns out that $0 was /usr/lib/dhcpcd/dhcpcd-run-hooks rather than my script. Apparently dhcpcd-run-hooks doesn't execute the script... it sources it. I made some changes to line 196 to fix this.
♔ Aaaaaand that seems to have fixed all problems. ♔
I'm trying to confirm that was the silver bullet now... I didn't notice it was working till I had made several other changes as well. If I can confirm it I'll submit an answer.
Complications
What complicates matters quite a bit is that it's original context is a /etc/dhcpcd.exit-hook script. dhcpcd-run-hooks appears to eat all stderr and stdout which makes troubleshooting... unpleasant. I've implemented my own logging utility to capture the output of commands in the script and pass it to journald but it's not helping in this case. Either no error is being generated or, somehow, the error is not getting captured by my logging utility. The script is running as root and there is no mandatory access control installed so it shouldn't be a permissions issue.
I have a ZIP file, not succeeded to unzip for some-reason, saying "invalid or incomplete multibytes or wide character". So I unzip -p myfile.zip > Messed.data , I want to separate them, with script.
unzip -l to get the files-size.
dd ibs=1 skip=$((sum of front file-size)) count=$((this-file-size))
I tried and found the speed was unbearable slow.
So I ask for any help to this. Thank you.
I am attempting to convert a directory full of .bmp files into a .mp4 file (or similar format).
The bitmap files have the following name scheme:
output_N_1024.bmp
Where N is an integer in the range 0 to 1023. (No zero padding / fixed width.)
The command I am using is:
avconv -r 25 -i output_{0..1023}_1024.bmp outputfile.mp4
This appears to run okay, and takes about a minute to convert all 1024, 1024 by 1024 resolution - (confusing?) bitmap images into a new file, outputfile.mp4.
However, when I attempt to open this file with VLC, a black window briefly flashes up and then closes. VLC then goes back to its mode where it waits for you to tell it which file to open next. No error or warning messages appear from VLC, which seems kind of strange since it seems to be refusing to play.
What can I do to fix this? Perhaps my converting command is incorrect?
The problem most likely is that you haven't actually passed the command to encode these files to avconv. This has happened because your shell has expanded the filenames already.
The command i have just managed to get to work on my machine is:
avconv -r 2 -i "%d.bmp" -s 600x400 -an out.ogv
Also for whatever reason it didn't want to work without explicitely giving it the size, but i don't think this is your problem.
In here quotes tell your shell not to touch this string. %d means digits from 1 to whatever the last file is (if you would want them to be 0-padded this would look like %000d to have maximum of three naughts in front).
VLC has then opened and ran my file just fine.
Please advise on replacing a variable with latest date & time.
Here is my requirement.
FN='basename$0'
TS=`date '+%m/%d/%Y %T'`
QD='08/27/2014 16:25:45'
Then I have a query to run. After it has run, I need to take $TS (current system date & time) and assign it as a value to the $QD variable. This is a loop process and gets updated every time the script runs.
I've tried using sed but was not successful.
Please help.
Programatically modifying your script to have a different timestamp constant is absolutely and emphatically the wrong way to handle this problem.
Instead, when you want to mark that the query has been done, simply touch a file:
touch lastQueryCompletion
...and when you want to know when the query was last done, check that file's timestamp:
# with GNU date
QD=$(date -r lastQueryCompletion '+%m/%d/%Y %T')
# or, with Mac OS X stat
QD=$(stat -t '%Y/%m/%d %H:%M:%S' -f '%Sm' lastQueryCompletion)
Although you haven't mentioned the overall goal that you wish to accomplish, I have a feeling something like this would be more robust than using sed to update an existing script file.
FN='basename$0'
TS=date '+%m/%d/%Y %T'
# Load the latest QD (from the last run)
[ -e ~/.QD.saved ] && QD="`cat ~/.QD.saved`"
QD='08/27/2014 16:25:45'
...Later in that file...
#Save the new QD variable
echo '$(date +$FORMAT)'" > ~/.QD.saved
Although I'm not sure if sed is the tool you're looking, I believe that your command would have to go like this:
sed -i -r 's/^QD=.*/QD="$TS"/g' "$FN"
I'm assuming you're using gnu-sed, which with -i option tells to do an in-place substitution, rather then copying the input line to the pattern space.
Well, hope it helps.