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Top Forums Programming Determining file access perms for current process Post 302467714 by jim mcnamara on Sunday 31st of October 2010 12:21:15 AM
Old 10-31-2010
All this is in the 'Art of UNIX Programming':
http://www.catb.org/esr/writings/tao...hing-guide.pdf
This was a small book for years, now it is a pdf online. Still available as a book, too.


A generally accepted guideline for language choice UNIX programming:

1. do it all in shell first.
2. if #1 won't work, don't use shell, resort to perl, python, ruby
3. if #2 won't work or speed is the primary requirement, don't use perl etc., use all C/C++

Going back up from C to shell kinda defeats having gone down to a compiled language to start with. What you are doing is calling another gigantic C program.

Note --

We have some extraordinary shell programmers here. See some of CFA Johnson's posts, or google his book. You can do a lot more than you realize just in shell. So going to #2 & #3 is not as common as you might think.

Also some shells like bash are easily extensible. Need a command - create your own builtin.
Using and Writing Bash Dynamically Loadable Built-In Commands by Chris F.A. Johnson
 

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URI::URL(3)						User Contributed Perl Documentation					       URI::URL(3)

NAME
URI::URL - Uniform Resource Locators SYNOPSIS
$u1 = URI::URL->new($str, $base); $u2 = $u1->abs; DESCRIPTION
This module is provided for backwards compatibility with modules that depend on the interface provided by the "URI::URL" class that used to be distributed with the libwww-perl library. The following differences exist compared to the "URI" class interface: o The URI::URL module exports the url() function as an alternate constructor interface. o The constructor takes an optional $base argument. The "URI::URL" class is a subclass of "URI::WithBase". o The URI::URL->newlocal class method is the same as URI::file->new_abs. o URI::URL::strict(1) o $url->print_on method o $url->crack method o $url->full_path: same as ($uri->abs_path || "/") o $url->netloc: same as $uri->authority o $url->epath, $url->equery: same as $uri->path, $uri->query o $url->path and $url->query pass unescaped strings. o $url->path_components: same as $uri->path_segments (if you don't consider path segment parameters) o $url->params and $url->eparams methods o $url->base method. See URI::WithBase. o $url->abs and $url->rel have an optional $base argument. See URI::WithBase. o $url->frag: same as $uri->fragment o $url->keywords: same as $uri->query_keywords o $url->localpath and friends map to $uri->file. o $url->address and $url->encoded822addr: same as $uri->to for mailto URI o $url->groupart method for news URI o $url->article: same as $uri->message SEE ALSO
URI, URI::WithBase COPYRIGHT
Copyright 1998-2000 Gisle Aas. perl v5.12.1 2008-04-04 URI::URL(3)
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