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Full Discussion: Read multiple lines at a time from file
Top Forums Shell Programming and Scripting Read multiple lines at a time from file Post 302828897 by rbatte1 on Wednesday 3rd of July 2013 12:38:02 PM
Old 07-03-2013
A tricky question indeed. It depends on what you are then going to go on and do, but if you are on AIX, there is a -p flag on grep to get you a paragraph. I'm not sure how many variants have it available through.

If the file is not large, you could:-
Code:
#!/bin/ksh
while read line
do
   if [ "$line" = "" ]
   then
      <handle new section>
   else
      <continue processing section>
   fi
done < file

It will be slow for larger files, but as an alternate you could split the file into multiple smaller ones based on the blank line, then process them in turn:-
Code:
#!/bin/ksh

mkdir $$
cd $$
typeset -Z12 i=0

linecnt=`grep -c file`
((linecnt=$linecnt+1))
csplit -n 6 ../file "/^$/" {$linecnt}

Then, loop through the files generated. You may need to consider the length of the file name counter (-n 6 in my example) and the red double dots are only if the file is in the current directory. You may have to adjust that to suit too.

You can then (because you are in a new directory with only your data in it) run a loop to process the files as you wish. I would recommend against a for file in * construct if you expect a lot of files as this may exceed the command line limit. You have the counter, so probably best to use that:-

Code:
typeset -Z12 file_num=0
while [ $file_num -le $linecnt ]
do
   ((file_num=$file_num+1))
   ....whatever....
done


If you are looking for just certain patterns, you could get a list of file names with a grep from this point and work through them too.



I hope that this helps.



Robin
Liverpool/Blackburn
UK
 

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LEARN ABOUT SUSE

irsend

IRSEND(1)								FSF								 IRSEND(1)

NAME

       irsend - basic LIRC program to send infra-red commands

SYNOPSIS

       irsend [options] DIRECTIVE REMOTE CODE [CODE...]

DESCRIPTION

       Asks the lircd daemon to send one or more CIR (Consumer Infra-Red) commands. This is intended for remote control of electronic devices such
       as TV boxes, HiFi sets, etc.

       DIRECTIVE can be:
	  SEND_ONCE	    - send CODE [CODE ...] once
	  SEND_START	    - start repeating CODE
	  SEND_STOP	    - stop repeating CODE
	  LIST		    - list configured remote items
	  SET_TRANSMITTERS  - set transmitters NUM [NUM ...]
	  SIMULATE	    - simulate IR event

       REMOTE is the name of a remote, as described in the lircd configuration file.

       CODE is the name of a remote control key of REMOTE, as it appears in the lircd configuration file.

       NUM is the transmitter number of the hardware device.

       For the LIST DIRECTIVE, REMOTE and/or CODE can be empty:

	  LIST	 ""    ""   - list all configured remote names
	  LIST REMOTE  ""   - list all codes of REMOTE
	  LIST REMOTE CODE  - list only CODE of REMOTE

       The SIMULATE command only works if it has been explicitly enabled in lircd.

       -h --help
	      display usage summary

       -v --version
	      display version

       -d --device
	      use given lircd socket [/var/run/lirc/lircd]

       -a --address=host[:port]
	      connect to lircd at this address

       -# --count=n
	      send command n times

EXAMPLES

	  irsend LIST DenonTuner ""
	  irsend SEND_ONCE  DenonTuner PROG-SCAN
	  irsend SEND_ONCE  OnkyoAmpli VOL-UP VOL-UP VOL-UP VOL-UP
	  irsend SEND_START OnkyoAmpli VOL-DOWN ; sleep 3
	  irsend SEND_STOP  OnkyoAmpli VOL-DOWN
	  irsend SET_TRANSMITTERS 1
	  irsend SET_TRANSMITTERS 1 3 4
	  irsend SIMULATE "0000000000000476 00 OK TECHNISAT_ST3004S"

FILES

       /etc/lirc/lircd.conf
	      Default lircd configuration file.  It should contain all the remotes, their infra-red codes and the corresponding timing	and  wave-
	      form details.

DIAGNOSTICS

       If lircd is not running (or /var/run/lirc/lircd lacks write permissions) irsend aborts with the following diagnostics:
       "irsend: could not connect to socket"
       "irsend: Connection refused" (or "Permission denied").

SEE ALSO

       The documentation for lirc is maintained as html pages. They are located under html/ in the documentation directory.

       lircd(8), mode2(1), smode2(1), xmode2(1), irrecord(1), irw(1), http://www.lirc.org.

irsend 0.8.7pre1						     May 2010								 IRSEND(1)
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