Shell Programming and Scripting

@alister, it would improve somewhat upon the accepted solution, since expr is an external command, whereas printf is not, although both would be slower than your suggested variable expansion of course.

Also $((10#$v)) is not available in every POSIX compliant shell like you stated

An advantage of the printf approach is that it would also handle cases like floating point and scientific notation and/or a leading plus signs..

Thank you all for your solutions
Looks like my little problem created quite an interesting discussion

Ken

Didn't I answer the question in post #4 in a way that others have replicated with more complex code?
I've written it as ksh, but the same works for bash

Not sure what all the worry is about.

For a faster process not reading line by line & looping, how about:-

Code:

sed s/^0*//g file

Does that fit the bill? It works for me.

I'd like to learn what I missed earlier and see if this is a better fit.




Robin

You didn't read post #3, did you?

So have I missed the point?
My reading of part of post #3:- This suggested to me that there was more data on the line, not that the file was just a single column of numbers, which is why I gave a solution for a file like this:-

Code:

0001
0002 123
0003 Hello

Ho hum, I suppose that it will work for either. Do we have a happy questioner? That's the important bit I suppose.


.... and hey, I've learnt a few techniques too, so I'm happy.


Robin

Hi robin we do have a happy Questioner :-)
Lots of great ideas and solutions in here.

the reason I did not want to run either sed or awk is that the number in question is clipped out of a much longer line ( as a string). this has to repeated for many lines in the original files. Shelling out to awk / sed will make the loop processing to complicated where doing as part of a string is relatively easy within the loop.

Also this is a bash script but for the original question that was not important, but certainly interesting to read the differences in the responses.

Ken