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# 15  
Old 08-01-2009
Print all variables - local and global.
Code:
set

Print global(=environment) variables. Child process get copy of global variables, but not locals.
Code:
env

What is locals ? set - env

How to make global variable ? Use export command.
Code:
export variable

How to remove variable ?
Code:
unset variable

How to look ex. IFS value, IFS include some special characters ? Example:
Code:
echo -n "$IFS" | od -c

IFS default value is "white space" = space+tab+newline

Using special characters. Example IFS is TAB+backspace+hex 02+newline
Code:
IFS=$'\t\b\x02\n'


One solution for your needs =remove all chars before ex. track007.mp3
= remove "07 - album - ". Space before string track.
Code:
#!/bin/ksh
#!/bin/bash

for f in *.mp3
do
    # remove all chars before last space including last space
    new="${f##* }"
    [ "$new" != "$f" ] && mv "$f" "$new"
done

Last edited by kshji; 08-01-2009 at 10:08 AM..
# 16  
Old 08-01-2009
Quote:
Originally Posted by Franklin52
Something like this?

Code:
ls *.mp3 | awk '{system("cp " $0 " " $NF)}'

I've used the cp command but you can replace it with the mv command.

Regards
Did not work for me
Code:
cp: target `track001.mp3' is not a directory
cp: target `track002.mp3' is not a directory
cp: target `track003.mp3' is not a directory
cp: target `track004.mp3' is not a directory
cp: target `track005.mp3' is not a directory
cp: target `track006.mp3' is not a directory
cp: target `track007.mp3' is not a directory
cp: target `track008.mp3' is not a directory
cp: target `track009.mp3' is not a directory

thanks anyway

I am trying something more bit complicated:
Code:
#!/bin/bash
#IFS=$'\n'
echo default IFS:
echo -n "$IFS" | od -a -b
IFS=$'\n'
echo new IFS:
echo -n "$IFS" | od -a -b
for x  in `ls *.mp3`
do
 echo "`sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp' $x`"
done
echo new IFS:
echo -n "$IFS" | od -a -b
unset IFS
echo standard IFS:
echo -n "$IFS" | od -a -b

but alsdo did not work, IFS is set to newline, sed command must be OK because if i try it outside script everything works. Now i tryed just echo output of sed but nothing appears.

also tried replace echo with
Code:
cp "$x" "`sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp' $x`"

but according expectation it do nothing.

Also i am noticed something strange
Code:
numbers="$(printf "\n")"; echo -n "$numbers" | od -a -b
0000000

numbers="$(printf "\t")"; echo -n "$numbers" | od -a -b
0000000  ht
        011
0000001

Can someone explain that ???


PS i am total bash scripting newbie, sorry for dummmy questions
Last edited by wakatana; 08-01-2009 at 02:02 PM..
# 17  
Old 08-01-2009
If all that you are trying to do is just rename the file,
then this is a simple and straight solution.
Code:
ls -1 | sed 's/.*\(track.*$\)/cp "&" \1/' | ksh

Doesthis solve your issue?
Or is it necessary it has to be done your way?
# 18  
Old 08-01-2009
I tried that but did not work this is error:
Code:
ksh[1]: 01: not found [No such file or directory]
ksh[2]: 02: not found [No such file or directory]
ksh[3]: 03: not found [No such file or directory]
ksh[4]: 04: not found [No such file or directory]
ksh[5]: 05: not found [No such file or directory]
ksh[6]: 06: not found [No such file or directory]
ksh[7]: 07: not found [No such file or directory]
ksh[8]: 08: not found [No such file or directory]
ksh[9]: 09: not found [No such file or directory]

Thanks anyway.

I am very interesting what is wrong with my script, for and sed works but when i put it together it does nothing.
# 19  
Old 08-01-2009
Quote:
Originally Posted by edidataguy
Code:
ls -1 | sed 's/.*\(track.*$\)/cp "&" \1/' | ksh

The -1 as an argument to ls is pointless if you are piping the result.

Anyway:
Code:
for file in *.mp3 ; do
      mv "$file" "${file##* }"
done

# 20  
Old 08-01-2009
Quote:
Originally Posted by reborg
The -1 as an argument to ls is pointless if you are piping the result.

Anyway:
Code:
for file in *.mp3 ; do
      mv "$file" "${file##* }"
done

Not that it affects the command in any way, but yes, the "-1" is not required.
I generally prefer 1 liner to run on the prompt and most of the requests are for that.
But, I do like your approach too.

---------- Post updated at 09:51 PM ---------- Previous update was at 09:37 PM ----------
Quote:
Originally Posted by edidataguy
If all that you are trying to do is just rename the file,
then this is a simple and straight solution.
Code:
ls -1 | sed 's/.*\(track.*$\)/cp "&" \1/' | ksh

Doesthis solve your issue?
Or is it necessary it has to be done your way?
Are you sure you gave the quotes in the "&"?
Ok. First try this and see what comes out:
Code:
ls *track* | sed 's/.*\(track.*$\)/cp "&" \1/'

If that looks good then try this:
Code:
ls *track* | sed 's/.*\(track.*$\)/cp "&" \1/' | ksh

But if you are not looking for an one liner, then the codeby Reborg looks more simpler.
# 21  
Old 08-02-2009
Reborg's solution works, thanks.
Edidataguy yes i type it properly (use copy and paste) but did not work, neither the
Code:
ls *track* | sed 's/.*\(track.*$\)/cp "&" \1/'

did not work.
But can somebody explain why my bash script with for did not work ? I am trying to learn something new in bash not ksh. thanks
Last edited by wakatana; 08-02-2009 at 09:43 AM..
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