Bash: remove oldest file

Hi,

I'm trying to remove the oldest file (whenever there's 14 or more):

Code:

		
		FILECOUNT=`ls | wc -l`;
		if [ $FILECOUNT > 14 ]
		then
			cd "$PATH" && ls -tr | head -n 1 | xargx rm -f;
			echo "Removed oldest file ...";
                else
			echo "No 14 files in the filesystem yet, nothing to remove";
		fi

I keep getting the following error though:

./mysqlbackup: line 1: ls: command not found
./mysqlbackup: line 1: wc: command not found
No 14 files in the filesystem yet, nothing to remove

Can anyone tell me what I'm doing wrong here ?

Thnx in advance !

PATH is a special variable. Apparently your script is overwriting its value and breaking path search. Never use a variable called PATH.

Yes, that was the problem, thnx

But it's not removing the file though .. is there any way to do this without xargx ? Cause it's not installed :\

Code:

cd "$PATH" && ls -tr | head -n 1 | read file &&  rm -f $file

Originally Posted by ReggieBE

Yes, that was the problem, thnx

But it's not removing the file though .. is there any way to do this without xargx ? Cause it's not installed :\

It's not xargx, it's xargs

lol ok thanks brewbuck and mcnamara, it's fixed !

Originally Posted by ReggieBE

lol ok thanks brewbuck and mcnamara, it's fixed !

You can do it without xargs OR read:

Code:

cd "$MY_PATH" && rm -f `ls -tr | head -n 1`

Those are backward single quotes, known as backticks. It takes the output of the pipeline within the backticks and substitutes it lexically into the command line. Very useful.

Code:

cd "$MY_PATH" && rm -f `ls -tr | head -n 1`

Those are backward single quotes, known as backticks. It takes the output of the pipeline within the backticks and substitutes it lexically into the command line. Very useful.

That's the old-style syntax. For POSIX compatibility, one should be using $() instead of ``:

Code:

cd "$MY_PATH" && rm -f $(ls -tr | head -n 1)

Besides portability (between newer systems, anyway), $() has several advantages. For example, you can nest them, unlike backquotes.

Originally Posted by dwks

That's the old-style syntax. For POSIX compatibility, one should be using $() instead of ``:

I don't really buy the portability argument. I don't know of any Bourne-style shell that does not understand the back ticks. However, I know of at least 4 systems within 100 feet of me that do NOT understand $().

So in practice, I use back ticks because it's more portable.

Besides portability (between newer systems, anyway), $() has several advantages. For example, you can nest them, unlike backquotes.

I'd call the inability to nest back ticks a feature, not a disadvantage. Nesting substitutions leads to an unreadable mess.

I don't really buy the portability argument.

How about portability between keyboards? Getting backticks on the console can be a real pain with German keyboards until the system is completely set up and tuned.

Backquotes are more portable now, simply because they have been around for a longer period of time. But POSIX-style shell substitution is part of the POSIX standard, and they make more sense anyway: the characters are easier to type, the characters are easy to distinguish (` can look like '), and they can be nested.

I would use the POSIX style unless the shell doesn't support it.