[linux] Adding timestamp to a filename with mv in BASH

Well, I'm a linux newbie, and I'm having an issue with a simple bash script.

I've got a program that adds to a log file while it's running. Over time that log file gets huge. I'd like to create a startup script which will rename and move the log file before each run, effectively creating separate log files for each run of the program. Here's what I've got so far:

pastebin

DATE=$(date +"%Y%m%d%H%M")
mv server.log logs/$DATE.log
echo program

When run, I see this:

: command not found
program

When I cd to the logs directory and run dir, I see this:

201111211437\r.log\r

What's going on? I'm assuming there's some syntax issue I'm missing, but I can't seem to figure it out.

UPDATE: Thanks to shellter's comment below, I've found the problem to be due to the fact that I'm editing the .sh file in Notepad++ in windows, and then sending via ftp to the server, where I run the file via ssh. After running dos2unix on the file, it works.

New question: How can I save the file correctly in the first place, to avoid having to perform this fix every time I resend the file?

mv server.log logs/$(date -d "today" +"%Y%m%d%H%M").log

A single line method within bash works like this.

[some out put] >$(date "+%Y.%m.%d-%H.%M.%S").ver

will create a file with a timestamp name with ver extension. A working file listing snap shot to a date stamp file name as follows can show it working.

find . -type f -exec ls -la {} \; | cut -d ' ' -f 6- >$(date "+%Y.%m.%d-%H.%M.%S").ver

Of course

cat somefile.log > $(date "+%Y.%m.%d-%H.%M.%S").ver

or even simpler

ls > $(date "+%Y.%m.%d-%H.%M.%S").ver

Well, it's not a direct answer to your question, but there's a tool in GNU/Linux whose job is to rotate log files on regular basis, keeping old ones zipped up to a certain limit. It's logrotate

I use this command for simple rotate a file:

mv output.log `date +%F`-output.log

In local folder I have 2019-09-25-output.log

You can write your scripts in notepad but just make sure you convert them using this -> $ sed -i 's/\r$//' yourscripthere

I use it all they time when I'm working in cygwin and it works. Hope this helps

First, thanks for the answers above! They lead to my solution.

I added this alias to my .bashrc file:

alias now='date +%Y-%m-%d-%H.%M.%S'

Now when I want to put a time stamp on a file such as a build log I can do this:

mvn clean install | tee build-$(now).log

and I get a file name like:

build-2021-02-04-03.12.12.log