How to delete .jpg file in linux console - linux

By accident I named my image file wrong so I wanted to delete it. So I typed the following in my linux console:
rm localapps\logo.jpg
But it didn't work.
Then I wrote
rm *.jpg
then it worked. Simple question. Why did the first not work , even I know that is the way to delete files in linux?

We would need the output of the commands you are running. You typically have no output when the command succeeds.
It is also important for you to notice that in linux, the / character is used to denote directories, and not \, which is actually typically the escape character.
In a terminal is also very important for you to notice in which directory are you working and what is the relative path to the file you want to refer to. You can find this out with the command pwd that stands for print working directory.
You would see something like
your-box:~ blurry$ pwd
/home/blurry
your-box:~ blurry$
This said, when you type
rm localapps\logo.jpg
since \ is a escape character, this is interpreted as
rm localappslogo.jpg
this means, it is looking for the file named localappslogo.jpg in the current directory (/home/blurry/localappslogo.jpg).
I assume that file does not exist, then, it will output something like:
rm: localappslogo.jpg: No such file or directory
when you type
rm *.jpg
this code removes any file ending in .jpg in the current directory. So notice that if you were trying to delete a file that was in the localapps folder, you should use instead
rm localapps/logo.jpg
But this is always assuming that the relative path to your image is localapps/logo.jpg.
You can also change directory then delete the file like this,
cd localapps
rm logo.jpg

Related

Renaming a script using Linux mv / rename

I'm trying to rename the script audience_segment_map.sh to audience_segment_map_dedupe.sh using the Linux command line.
I have tried using the mv and the rename commands but they're not having the desired effect:
mv user/local/dmp_job/audience_segment_map.sh user/local/dmp_job/audience_segment_map_deupe.sh
This returns the error
'audience_segment_map.sh' No such file or directory"
but when I use the ls command, the file clearly shows up.
How should I proceed?
Pointing to a path with and without leading / slashes are different (absolute versus relative, respectively). Unless you are in the root directory, most likely you want your command to look like
mv /user/local/dmp_job/audience_segment_map.sh /user/local/dmp_job/audience_segment_map_deupe.sh
where the path is pointing to /user/local/... instead of user/local/...

cant delete file using variable name in shell script

I want to delete a file whose name is stored in a variable, but it doesn't work. I'm getting
A file or Directory in the path name does not exist
My code is
value=$(<try_text.txt)
rm -f /home/inform/output/$value
when i tried deleting i got :
cannot remove `/home/oracle/Omar2/B2BFiles/bm.txt\r': No such file or directory
where does the \r come from ?
It comes from an editor which wrote the Windows line ending \r\n to try_text.txt. When reading that file, the Linux shell removed the Unix line ending \n, and the \r remained. To get rid of it, see e. g. the answers to the question Line ending issue DOS > Linux > Java.
Try this:
value=try_text.txt
rm -f /home/inform/output/$value
Don't run the value variable in a subshell when it's not needed.
EDIT
Previously misunderstood the question, didn't see the '<'.
This works on my system:
value=$(</home/user/Documents/try_text.txt)
rm -f /home/user/Documents/$value
as #gile said, make sure the try_text.txt is in your working directory.

The output of ls with -aF option is not clear

When I try the command ls with -aF option inside any directory whether it's empty or not, I always got the following:
./ ../
so what does the output mean when I have these two options together with ls command?
When you use ls, you are reading a directory file, not actually looking in a directory. Every directory listing contains an entry for the present/current directory, as well as its parent directory, just as you would expect to also see listings for sub/child directories in any directory listing.
The -A option for ls merely tells ls to display ALL files, which includes the entries of ./ & ../ for present and parent. Note that these dots are merely a shorthand that the shell (bash) uses to represent file paths for those files. In other words, what "./" really means is say ~/Desktop if you were currently in the Desktop directory doing an ls. And "../" would mean "~/" which is just another symbolic shorthand to represent your user home directory, which is probably something like /Users/your_username on macOS (OS X), or /usr/your_username for various Linux distributions. Note that those paths could also be written with the forward slash appended at the end and would mean the same thing (e.g., /Users/your_username/ is the same as /Users/your_username because they are both references to other directories (directory files).
Use the -a option for ls if you don't want to see ./ & ../, but still want to see (other) hidden files.
Using the -F option causes ls to display appended characters to the file types based on the file type. This is why directories are displayed with the forward slash appended at the end, and executables are displayed as executable* (with the asterisk appended), and regular files have no appendage (e.g., .txt, .png, .dmg).

How to delete all files in one particular directory

In Linux, how can I delete all files in particular directory? For example /home/xd/karthik is my path; I want to delete all files in the above directory, if the disk usage exceeds 90%. How can I write a script for that?
rm /path/to/directory/*
add rm -r to remove the file hierarchy rooted in each file argument.
dont need script just basic shell command

shell script : appending directory path and filename

I want to copy a file from a directory using shell script
Suppose I save the directory and file name seperately as
dir=/home/user/directory/
file=file_1
to copy the file Im using this command in my script
cp $dir$file .
But I get this error
/bin/cp omitting directory '/home/user/directory'
I have tried all combination eg. omitted the trail backslah from variable dir, etc but nothings working. I cant understand what is wrong with this code. Pleas help
Maybe the command $dir$file is not getting unpacked in the shell (ie only the directory variable is getting unpacked, not the file variable)!!!!!
It looks like you are having problem with expansion in cp $dir$file . In order to prevent possible problems, it is better to protect your variable with braces and double quote the full path/file to make sure you don't get caught by spaces in either the filename or heaven forbid the user's dirname:
cp "${dir}${file}" .
This will prevent the possibility the second $ is missed. Also make sure you have read access to other users /home (if you are root or using sudo you should be fine)
If you see this, when you somehow assign an empty string to file somewhere. Search your script for file= and unset file.
You can also debug this by adding
echo ".${file}."
in the line before the cp command. I'm pretty sure it prints .., i.e. the variable is empty or doesn't exist.

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