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Full Discussion: help with an if expression..
Top Forums Shell Programming and Scripting help with an if expression.. Post 302607143 by Telis on Tuesday 13th of March 2012 06:42:27 PM
Old 03-13-2012
help with an if expression..
hello everyone.. as i said in a previous thread again, im new in linux shell programming and i came up with a new problem i cant solve. so i need your help..

this is the code
Code:
#!/bin/sh
a=0
while [ "$a" -lt 100 ]
do
a=`expr $a + 1`
b=$(( 3 * $a ))
if [ "$a" == "$b" ] ; then
continue
fi
echo "$a"
done

what im trying to do here is display the numbers 1 2 4 5 7 8 10 11 14 15 ....
my code isnt working correctly.. when i run it like this,i get all the numbers displayed even those i dont want (3 6 9 12 etc) and i also get the message unexpected operator after every number..

and when i run it like this
Code:
#!/bin/sh
a=0
while [ "$a" -lt 100 ]
do
a=`expr $a + 1`
b=$(( 3 * $a ))
if [ $a -eq $b ] ; then
continue
fi
echo "$a"
done

i just have all the numbers displayed.. 1 2 3 4 5 6 7 8 9 10... even those i dont want.. so the code is not working correctly..
where is the mistake? im pulling my hair off!
 

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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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