Script to mimic the tree command

**demonkingj** · March 24th, 2012

So I am just wanting to mimic the tree command.
sample:

Code:

/etc/gdm
|-- Init
| '-- Default
|-- PostLogin
| '-- Default.sample
|-- PostSession
| '-- Defaul t
|-- PreSession
| '-- Default
|-- Xses s ion
|-- failsafeBlacklist
|-- failsafeDexconf
|-- failsafeXServer
|-- failsafeXinit
‘-- gdm.schemas
4 directories, 10 files

I am fairly new to scripting.
I understand I need to iterate through each directive. I found that typing

Code:

dir -B1 path

is what I need, but I can't really pin point each directory with that.

I have done my positional parameters if

Code:

mytree [blank] [ --help] [directory]

if blank then search from current directory which I can check with pwd.
if --help, conditional statement to display help command and if chosen directory then just start at that directory.

I just don't know how to 'pin point' a directory then search through all it's directories, and so on.

I have been using http://linuxcommand.org/writing_shell_scripts.php and http://www.gnu.org/software/bash/man...ode/index.html, but haven't seen anything that could help me.

**Jest3r** · March 25th, 2012

Hello & Welcome,

It sounds like you are replicating the functionally of the find command ( awesome, but complex command )

Code:

 $ find /etc/gdm -name Default
/etc/gdm/PreSession/Default
/etc/gdm/PostSession/Default
/etc/gdm/Init/Default

If you are looking to iterate (or loop) over a list of files in a directories you can use the for command.

A very common pattern is for is the following...

Code:

$ for i in `ls /etc/gdm`
> do
> echo "Found file: $i"
> done
Found file: custom.conf
Found file: gdm.schemas
Found file: Init
Found file: PostLogin
Found file: PostSession
Found file: PreSession
Found file: Xsession

Is this what you are after ?

**demonkingj** · March 25th, 2012

Originally Posted by Jest3r

Hello & Welcome,

It sounds like you are replicating the functionally of the find command ( awesome, but complex command )

Code:

 $ find /etc/gdm -name Default
/etc/gdm/PreSession/Default
/etc/gdm/PostSession/Default
/etc/gdm/Init/Default

If you are looking to iterate (or loop) over a list of files in a directories you can use the for command.

A very common pattern is for is the following...

Code:

$ for i in `ls /etc/gdm`
> do
> echo "Found file: $i"
> done
Found file: custom.conf
Found file: gdm.schemas
Found file: Init
Found file: PostLogin
Found file: PostSession
Found file: PreSession
Found file: Xsession

Is this what you are after ?

thanks for the welcome and response.the find command does seem helpful, but wouldn't help me in this situation. I don't know the name of the file.

The for command doesn't seem to work for me. It just outputs File found: ls /etc/gdm it didn't work like what you posted.

But this is how it should be I will explain.

Begin to execute.
If no parameters start at current directory ( pwd ). Search through it's sub-directories, files, and then if there is another directory go into it's sub-directories. If that directories sub-directory has ended go to the previous directory and continue the whole process above.

Once no more files or directories are left.
Tally up the total number of directories and files.

IF there is a parameter, path, then start at that path.

I just don't know the code to make this happen.

**Jest3r** · March 25th, 2012

Is this what your after?

I created a script called "file_count.bash" with the following contents

Code:

#!/bin/bash
DIR=${1}||$PWD
find $DIR | wc -l

Giving the script an argument it counts all the files and directories for that directory

Code:

$ ./file_count.bash /etc/gdm/
12

With no argument it counts all the files and directories in the current directory ( or pwd )

Code:

$ ./file_count.bash 
123175

Sorry if I have misunderstood what your after.

**demonkingj** · March 25th, 2012

Originally Posted by Jest3r

Is this what your after?

I created a script called "file_count.bash" with the following contents

Code:

#!/bin/bash
DIR=${1}||$PWD
find $DIR | wc -l

Giving the script an argument it counts all the files and directories for that directory

Code:

$ ./file_count.bash /etc/gdm/
12

With no argument it counts all the files and directories in the current directory ( or pwd )

Code:

$ ./file_count.bash 
123175

Sorry if I have misunderstood what your after.

I am also trying to display the files as well, but wanting to assign each file or directory to a variable.

So i can do this
variable = file/directory
if [ -d $variable]; then
echo 'something'
elif [-f $variable]; then
echo 'something else'

These if statements is to display a tree-like structure like the example post from the initial post

**codemaniac** · March 25th, 2012

Hello demonkingj ,
Try the below script that would create a tree of directories under current directory .

Code:

#!/bin/bash

olddir=$PWD;
color="off";
for option in "$@"
do
    case $option in
        --color ) color="on";
              shift;;
        -*    ) shift;;
        *       )      ;;
    esac
done
declare -i stackheight=0;

function listf {
    cd "$1";
    for file in *
    do
        for ((i=0; $i < $stackheight; i++))
        do
            printf "\t";
        done
        if [ -d "$file" ]
        then
            if [ $color == "on" ]
            then
                printf "\e[34m";
            fi
        fi
        printf "$file\e[0m\n";
        if [ -d "$file" ]
        then
            stackheight=$stackheight+1;
            listf "$file";
            cd ..;
        fi
    done
    let stackheight=$stackheight-1;
}
listf "$1";
cd $olddir;
unset i color stackheight;

**demonkingj** · March 25th, 2012

Originally Posted by codemaniac

Hello demonkingj ,
Try the below script that would create a tree of directories under current directory .

Code:

#!/bin/bash

olddir=$PWD;
color="off";
for option in "$@"
do
    case $option in
        --color ) color="on";
              shift;;
        -*    ) shift;;
        *       )      ;;
    esac
done
declare -i stackheight=0;

function listf {
    cd "$1";
    for file in *
    do
        for ((i=0; $i < $stackheight; i++))
        do
            printf "\t";
        done
        if [ -d "$file" ]
        then
            if [ $color == "on" ]
            then
                printf "\e[34m";
            fi
        fi
        printf "$file\e[0m\n";
        if [ -d "$file" ]
        then
            stackheight=$stackheight+1;
            listf "$file";
            cd ..;
        fi
    done
    let stackheight=$stackheight-1;
}
listf "$1";
cd $olddir;
unset i color stackheight;

Thank you for the reply. Could you please explain this to me? I understand a good portion, but haven't seen some of this code like..
declare, i assume it "declares" variable '-i' is integer?
for option @ thing i don't understand at all
the case thing i am not sure about that either.
Unset i color as well.

**Vaphell** · March 25th, 2012

"$@" means list of all supplied parameters
that code block is supposed to recognize options and set things up. For loop iterates over the param list and case tests current option against --color, -<anything> and <anything> and does things.

Code:

#!/bin/bash

for option in "$@"
do
   case $option in
      --color ) echo "'$option' matches --color";;
      -*      ) echo "'$option' matches -*";;
      *       ) echo "'$option' matches *";;
    esac
done

test:

Code:

./args.sh --color --color-range -xyz 1 -t 2
'--color' matches --color
'--color-range' matches -*
'-xyz' matches -*
'1' matches *
'-t' matches -*
'2' matches *

What i find strange is the existence of shift there. I don't think it does anything in case of for loop.
Shift removes $1 from param list and other params move to the front ($2 becomes $1). It is usually used with while loop, you test against non-empty list, analyze $1 and then shift.

Code:

while (( $# ))
do
  echo "$# parameter(s) remaining"
  case $1 in
    --color ) echo "'$1' matches --color";;
    -*      ) echo "'$1' matches -*";;
    *       ) echo "'$1' matches *";;
  esac
  shift
done

Code:

./args2.sh --color --color-range -xyz '--color aaa' -t 2
6 parameter(s) remaining
'--color' matches --color
5 parameter(s) remaining
'--color-range' matches -*
4 parameter(s) remaining
'-xyz' matches -*
3 parameter(s) remaining
'--color aaa' matches -*
2 parameter(s) remaining
'-t' matches -*
1 parameter(s) remaining
'2' matches *

while seems more powerful. Let's say you use some option with -switch value combo. You can conveniently take care of (-switch) and following (value) at once which would be more complicated in for loop

Code:

-switch ) option_a=on; shift; option_a_param=$1;

**codemaniac** · March 26th, 2012

Although rarely used, the bash declare statement does have a couple useful options. It can mark a variable as read only and also mark it as being a number only.

To declare a variable as read only, use the following statement:

Code: