Shell Programming and Scripting

Hi,

I am writing an ebuild for Gentoo Linux operating system.

Writing an ebuild is about Bash scripting where I am a newbie.

So, my ebuild must find a part of a specific filename.
Such a filaname my look like this:

Code:

libvclient_release_x64.so.740

and I must to find the number at the and of filename, which is in this case 740.

This number will change with time ( eg. it was a few days ago 734 ) so my ebuild must find it to works properly.

If I can to find this part of filename, then I can to store it into a variable which can then use further in the ebuild script.

The file path is known for my ebuild script but the filename can change, but only that number at the end of filename.

How can I find that part of the filename?

Best, Pál

Code:

specific_filename=libvclient_release_x64.so.740

number=${specific_filename##*[.]}

It works,

Code:

echo ${number}

gives

Code:

740

But what I want is the following.
How can I find the number - in this case the 740 - if I do not know the full specific_filename?
Eg. I know only the 'libvclient_release_x64.so.' part of the filename, but do not know the last '740' part of it, and want to find that unknown part?

Code:

specific_filename=libvclient_release_x64.so.*

does not do the job.

Hello csanyipal,

Welcome to forums, I hope you will enjoy learning and sharing knowledge here. Could you please try following and let me know if this helps you.

Code:

filename="libvclient_release_x64.so.740"
val=$(cut -d"." -f3 <<<$filename)
echo $val
740

EDIT: Adding this solution after seeing your POST#2, let me know if this helps you.

Code:

awk 'FNR==1{if(name){close(name)};split(FILENAME, a,".");print a[3];name=FILENAME;nextfile}' libvclient_release_x64.so.*

Thanks,
R. Singh

It works, thank you.
I wonder if it works if the filname will change so, so the number at the and will change into four digit number too?

Hello csanyipal,

Glad that it helped you. You could HIT THANKS button at left most corner of each post if you find any post useful. Off course above will not work for every file name. Since you have provided pattern specific file patterns so I had written as per that file name(s). You may need to change the pattern of file(s) in case your name changes too.

Let me know if you have any queries on same.

Thanks,
R. Singh

I am trying to use this in my ebuild:

Code:

lvcltno=awk 'FNR==1{if(name){close(name)};split(FILENAME, a,".");print a[3];name=FILENAME;nextfile}' \
           opt/VServer/vcomponents/libvclient_release_x64.so.*

dosym libvclient_release_x64.so."${lvcltno}" "${EPREFIX}/usr/$(get_libdir)/libvclient_release_x64.so"

but it does not work, the symlink is not created properly:

Code:

libvclient_release_x64.so -> libvclient_release_x64.so.

It seems that that the link is pointing to it self. Why? How can I fix this?