[SOLVED] [BASH] Find + sed --> can you pipe variables?

RaptorX · 08-29-2009, 06:46 AM

Hi...

I am writing a little script and i use this to list some files in the working directory:

Code:

find $img_dir -maxdepth 1 -type f

well the issue is that the list contains the path + the name of the file... I wanted to just get the filenames...

I thought of something like:

Code:

find $img_dir -maxdepth 1 -type f | sed "s/$img_dir//"

it didnt work it gives me errors like:

Code:

sed: -e expression #1, char 9: unknown option to `s'

but if I use an environment variable like $PWD sed works fine... the question is is it possible to pipe a normal variable? or is there any other way to do what im looking for? (well this is linux there ARE tons of ways of doing EVERYTHING ...

)

Thanks

jschiwal · 08-29-2009, 06:52 AM

Look in the find info manual for -printf and the directives it uses.

find $DIR -type f -printf '%f\n'

I usually need to go back to the info manual to remember which directive to use.
Using -printf, you have a lot of control over the output format.

JulianTosh · 08-29-2009, 06:57 AM

it's failing because there's probably a '/' in $img_dir.

how about this..

Code:

pushd $img_dir
find . -maxdepth 1 -type f | sed "s/\.\///"
popd

JulianTosh · 08-29-2009, 06:58 AM

Quote:

Originally Posted by jschiwal

find $DIR -type f -printf '%f\n'

Ohh i like that!

colucix · 08-29-2009, 07:01 AM

In sed the slash as a delimiter for the substitute command is not mandatory. You can use any other character: the first one after the s command will be used as delimiter. These all are valid:

Code:

sed "s%$img_dir%%"
sed "s@$img_dir@@"

and so on. I prefer the solution by jschiwal, anyway.

RaptorX · 08-29-2009, 07:18 AM

Quote:

Originally Posted by colucix

In sed the slash as a delimiter for the substitute command is not mandatory. You can use any other character: the first one after the s command will be used as delimiter. These all are valid:

Code:

sed "s%$img_dir%%"
sed "s@$img_dir@@"

and so on. I prefer the solution by jschiwal, anyway.

Interesting... I will be diving in to sed and awk soon, but that is cool to know since a lot of scripts that i have seen use the @ delimiter and i was confused about it...

if i use sed s%$img_dir%% it works perfectly.

and yes: find . -printf "%f\n"
the best solution here.

JulianTosh · 08-29-2009, 07:21 AM

Quote:

Originally Posted by RaptorX

sed s%$img_dir%% it works perfectly.

I had no idea sed allowed this. Always fun to learn something new like this.

BTW, it works perfectly up until $img_dir contains a %

jschiwal's printf for the win...

RaptorX · 08-29-2009, 08:00 AM

yes, but i am yet to find the -printf's directives in "info find", I found very general information there.

JulianTosh · 08-29-2009, 08:16 AM

use 'man find' and search for printf...

Quote:

%b File’s size in 512-byte blocks (rounded up).

%c File’s last status change time in the format returned by the C ‘ctime’ function.

%Ck File’s last status change time in the format specified by k, which is the same as for %A.

%d File’s depth in the directory tree; 0 means the file is a command line argument.

%f File’s name with any leading directories removed (only the last element).

%F Type of the filesystem the file is on; this value can be used for -fstype.

%g File’s group name, or numeric group ID if the group has no name.

%G File’s numeric group ID.

%h Leading directories of file’s name (all but the last element).

%H Command line argument under which file was found.

%i File’s inode number (in decimal).

%k File’s size in 1K blocks (rounded up).

%l Object of symbolic link (empty string if file is not a symbolic link).

%m File’s permission bits (in octal).

%n Number of hard links to file.

%p File’s name.

%P File’s name with the name of the command line argument under which it was found removed.

%s File’s size in bytes.

%t File’s last modification time in the format returned by the C ‘ctime’ function.

%Tk File’s last modification time in the format specified by k, which is the same as for %A.

%u File’s user name, or numeric user ID if the user has no name.

%U File’s numeric user ID.

%Z (SELinux only) file’s security context.

RaptorX · 08-29-2009, 08:48 AM

ah! I thought that i had to do "info find" instead of "man find"... thanks for the pointers!