10-02-2001
Shell Implementation
I want to implement my own simple multi tasking shell in Unix which will take care of redirection (<, >, >>) and piping.
I am just unable to get a concrete idea of how exactly I have to start. I have several books...some are..
1. Maurice Bach- Design Of Unix Operating System
2. Richard Stevens- Advanced Programming in Unix
However I find the language too high and complicated in these books.
Can someone please suggest how exactly I should go abt it...(step by step)
What are the things that I need to Learn to Implement this?
(anything and everything)
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LEARN ABOUT SUSE
mail::spamassassin::plugin::autolearnthreshold
Mail::SpamAssassin::Plugin::AutoLearnThreshold(3) User Contributed Perl Documentation Mail::SpamAssassin::Plugin::AutoLearnThreshold(3)
NAME
Mail::SpamAssassin::Plugin::AutoLearnThreshold - threshold-based discriminator for Bayes auto-learning
SYNOPSIS
loadplugin Mail::SpamAssassin::Plugin::AutoLearnThreshold
DESCRIPTION
This plugin implements the threshold-based auto-learning discriminator for SpamAssassin's Bayes subsystem. Auto-learning is a mechanism
whereby high-scoring mails (or low-scoring mails, for non-spam) are fed into its learning systems without user intervention, during
scanning.
Note that certain tests are ignored when determining whether a message should be trained upon:
o rules with tflags set to 'learn' (the Bayesian rules)
o rules with tflags set to 'userconf' (user configuration)
o rules with tflags set to 'noautolearn'
Also note that auto-learning occurs using scores from either scoreset 0 or 1, depending on what scoreset is used during message check. It
is likely that the message check and auto-learn scores will be different.
USER OPTIONS
The following configuration settings are used to control auto-learning:
bayes_auto_learn_threshold_nonspam n.nn (default: 0.1)
The score threshold below which a mail has to score, to be fed into SpamAssassin's learning systems automatically as a non-spam
message.
bayes_auto_learn_threshold_spam n.nn (default: 12.0)
The score threshold above which a mail has to score, to be fed into SpamAssassin's learning systems automatically as a spam message.
Note: SpamAssassin requires at least 3 points from the header, and 3 points from the body to auto-learn as spam. Therefore, the
minimum working value for this option is 6.
perl v5.12.1 2010-03-16 Mail::SpamAssassin::Plugin::AutoLearnThreshold(3)