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Full Discussion: communication between shell and and a demon 'c' program
Top Forums Shell Programming and Scripting communication between shell and and a demon 'c' program Post 302541749 by kshji on Monday 25th of July 2011 02:36:22 PM
Old 07-25-2011
Also event method is nice. daemon is trivial and not poll anything if both: daemon + client use signals = very hw friendly.

Daemon:
Code:
sometodo()
{
   # do the client files
   :
}

trap 'sometodo' 2
while true
do
        sleep 10000
done

Daemon trap some signal ex. 2 in previous code.

Client create some own file like $$.mydata.ask:
Code:
MYPID=$$
MYNEED=I/1/34/5
MYANSWERFILE=$$.mydata.answer

Then send signal for daemon
Code:
kill -2  $DAEMONPID

Then daemon catch the signal 2 and read some directory.
There is NNN.mydata.ask files
Run those files in same process:
Code:
.  NNN.mydata.ask
echo "$(date '+%Y%m%d%H%M%S') NNN.mydata.ask" >> somelog
cat NNN.mydata.ask >> somelog
rm -f NNN.mydata.ask

Then do the ...
And write answer to the file $MYANSWERFILE.tmp
and give the answer for client which poll this file

Code:
mv $MYANSWERFILE.tmp $MYANSWERFILE

Ofcourse it's also possible that client create subprocess, give that PID number for daemon. Daemon send signal for that dummy process.
Child wait that process to end.

Client version, wait signal from daemon:
Code:
somechild &
CHILD=$!
cat <<EOF > $$.mydata.ask
MYPID=$$
MYNEED=I/1/34/5
MYANSWERFILE=$$.mydata.answer
SENDSIGNAL2PID=$CHILD
EOF

kill -2 $DAEMONPID
wait $CHILD

 

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LEARN ABOUT MOJAVE

locale::codes::langfam

Locale::Codes::LangFam(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangFam(3pm)

NAME

       Locale::Codes::LangFam - standard codes for language extension identification

SYNOPSIS

	  use Locale::Codes::LangFam;

	  $lext = code2langfam('apa');		       # $lext gets 'Apache languages'
	  $code = langfam2code('Apache languages');    # $code gets 'apa'

	  @codes   = all_langfam_codes();
	  @names   = all_langfam_names();

DESCRIPTION

       The "Locale::Codes::LangFam" module provides access to standard codes used for identifying language families, such as those as defined in
       ISO 639-5.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 639-5
       language family codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying language families. A code set may be specified using either a name, or a
       constant that is automatically exported by this module.

       For example, the two are equivalent:

	  $lext = code2langfam('apa','alpha');
	  $lext = code2langfam('apa',LOCALE_LANGFAM_ALPHA);

       The codesets currently supported are:

       alpha
	   This is the set of three-letter (lowercase) codes from ISO 639-5 such as 'apa' for Apache languages.

	   This is the default code set.

ROUTINES

       code2langfam ( CODE [,CODESET] )
       langfam2code ( NAME [,CODESET] )
       langfam_code2code ( CODE ,CODESET ,CODESET2 )
       all_langfam_codes ( [CODESET] )
       all_langfam_names ( [CODESET] )
       Locale::Codes::LangFam::rename_langfam  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::LangFam::add_langfam  ( CODE ,NAME [,CODESET] )
       Locale::Codes::LangFam::delete_langfam  ( CODE [,CODESET] )
       Locale::Codes::LangFam::add_langfam_alias  ( NAME ,NEW_NAME )
       Locale::Codes::LangFam::delete_langfam_alias  ( NAME )
       Locale::Codes::LangFam::rename_langfam_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangFam::add_langfam_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangFam::delete_langfam_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.loc.gov/standards/iso639-5/id.php
	   ISO 639-5 .

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 2011-2013 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.18.2							    2013-11-04					       Locale::Codes::LangFam(3pm)
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