Warp wrote:

>   The shell doing the expansion rather than the program is a rather clever
> idea.

Yeah. But then, it's part of the general Unix philosophy of "make each 
tool do one job, and one job well".

With MS-DOS/Windows, the shell's job is basically to launch the 
interactive programs that do all the *real* work. The shell itself is 
pretty poor. (Although not quite as poor as it seems at first...)

>> I'm still not seeing what's so useful about being able to search a file 
>> for something.
> 
>   Suppose that you have a httpd log file and you want to list all entries
> within a specific day. Or the number of requests for a specific file (or
> a group of files). Suppose you want to list all entries *except* those
> which match a certain pattern (eg. they have a referrer which indicates
> that the request was made by a search engine). 'grep' is your tool for that.

Ah, right. I see.

Personally, I'd import the whole log into a relational database, and 
process it that way. (Or maybe even use a webserver that keeps its logs 
in a database in the first place, rather than a huge flat file.) But 
apparently that's just me...

>> Now, I suppose if you were trying to script something, being able to 
>> pipe output from another command into grep so that it can grab a 
>> particular substring that you can then pipe to something else might be 
>> useful. But then, if *I* wanted to do something like that, I wouldn't 
>> script it. I'd write a real program, not a script.
> 
>   Filtering some files through a chain of programs (such as grep and sed)
> takes just a few seconds of writing a few commands on the command line.
> Writing a program to do that would probably take a hundred times longer.

On the contrary, figuring out how to work grep vs writing a program in a 
language I already know well is likely to take *slightly* more than 
merely a hundred times longer. (Although you could argue that's a 
one-time cost.)

Personally I just dislike scripting languages. I'd rather use a real 
language with propper error checking and so on and so forth. But I guess 
that's just me.

>> I never have 50 small files.
> 
>   Haha. You are quite humorous sometimes.

Maybe I just don't try to do the same kinds of tasks as you?

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