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String/Variable Concatenation

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# 1  
Old 03-07-2010
String/Variable Concatenation
Hello,

Trying to concatenate the following using bourne shell:

Code:
# !/bin/bash
# this works in bash shell e.g. get the results I am expecting
fnTmp=C$cindex.$station_0.$station_1.$station_3.$ts.tmp
#
# under !/bin/sh
# the results are not the same

Any assistance would be appreciated...
# 2  
Old 03-07-2010
Quote:
Originally Posted by LAVco
Hello,

Trying to concatenate the following using bourne shell:

Code:
# !/bin/bash
# this works in bash shell e.g. get the results I am expecting
fnTmp=C$cindex.$station_0.$station_1.$station_3.$ts.tmp
#
# under !/bin/sh
# the results are not the same


What are the results? How do they differ?

I see nothing there that will vary from one shell to another.

Unless the problem is exported variables. In a Bourne shell, values may not be exported unless you do it explicitly at each level. In bash, once a variable is exported, it doesn't need to be exported again in its children.
# 3  
Old 03-07-2010
thanks for the response..

in bash the result is C1.NL.NLDOT.NLPCP.20100307T052700.tmp

In bourne the result is .20100307T052700.tmp

---------- Post updated at 01:42 AM ---------- Previous update was at 01:40 AM ----------

additional info..

Code:
#
cfgFilePath="../etc/app.conf"
#
# configuration section constants
cfgSec0="STATION"
cfgSec1="NETWORK-CAMERA"
cfgSecCnt1=`grep -c $cfgSec1 $cfgFilePath`
cfgSec2="DATA-CENTER"
cfgSecCnt2=`grep -c $cfgSec2 $cfgFilePath`
#
# timestamp
ts=`date --utc +%Y%m%dT%H%M00`
#
# parse station parameters
set -- $(awk '/\['$cfgSec0']/{f=1;next}/\[/{f=0}f{print $NF}' $cfgFilePath)
#
sta_region=$1
sta_org=$2
sta_name=$3
sta_clientid=$4
sta_netid=$5
#
for (( i = 0 ; i < cfgSecCnt1 ; i++ )); do
	# set camera index value
	cindex=$[$i + 1]
	echo $cindex
	echo $sta_region 
	echo $sta_org 
	echo $sta_name 
	echo $sta_clientid
	echo $sta_netid
	echo ""
	# create temp and actual file name
	fnTmp=("C"$cindex"."$sta_region"."$sta_org"."$sta_clientid"."$ts".tmp")
	#
	#echo "C $cindex . $sta_region . $sta_org"
	echo $fnTmp
	#
	# parse network-camera parameters
	set -- $(awk '/\['$cfgSec1'.C'$cindex']/{f=1;next}/\[/{f=0}f{print $NF}' $cfgFilePath)
	#
	cam_uid=$1
	cam_pwd=$2
	cam_host=$3
	cam_cmd=$4
	echo $4
done

# 4  
Old 03-07-2010

Have the variables been exported in the calling script?


---------- Post updated at 12:48 AM ---------- Previous update was at 12:43 AM ----------
Quote:
Originally Posted by LAVco
thanks for the response..

in bash the result is C1.NL.NLDOT.NLPCP.20100307T052700.tmp

In bourne the result is .20100307T052700.tmp

---------- Post updated at 01:42 AM ---------- Previous update was at 01:40 AM ----------

additional info..

Code:
for (( i = 0 ; i < cfgSecCnt1 ; i++ )); do


That is not Bourne shell syntax, so it cannot work in a Bourne shell.
Quote:
Code:
	fnTmp=("C"$cindex"."$sta_region"."$sta_org"."$sta_clientid"."$ts".tmp")


That is not Bourne shell syntax.
# 5  
Old 03-07-2010
no (not that I am aware of), single script being called within an ARM SBC.

---------- Post updated at 01:52 AM ---------- Previous update was at 01:48 AM ----------

oddly the loop works before I tried concatenating the string. variables are being read until I try to build the filename.

I have #!/bin/sh declared and no errors are being generated.

---------- Post updated at 02:07 AM ---------- Previous update was at 01:52 AM ----------

I've removed the the 'for' loop and getting the same result.

Code:
#
cfgFilePath="../etc/app.conf"
#
# configuration section constants
cfgSec0="STATION"
cfgSec1="NETWORK-CAMERA"
cfgSecCnt1=`grep -c $cfgSec1 $cfgFilePath`
cfgSec2="DATA-CENTER"
cfgSecCnt2=`grep -c $cfgSec2 $cfgFilePath`
#
# timestamp
ts=`date --utc +%Y%m%dT%H%M00`
#
# parse station parameters
set -- $(awk '/\['$cfgSec0']/{f=1;next}/\[/{f=0}f{print $NF}' $cfgFilePath)
#
staRegion=$1
staOrg=$2
staName=$3
staClientId=$4
staNetId=$5
#
echo $staRegion 
echo $staOrg 
echo $staName 
echo $staClientId
echo $staNetId
echo ""
# create temp and actual file name
fnTmp=C1.$staRegion.$staOrg.$staClientId.$ts.tmp
#
echo $fnTmp

# 6  
Old 03-07-2010
Quote:
Originally Posted by LAVco
Code:
fnTmp=("C"$cindex"."$sta_region"."$sta_org"."$sta_clientid"."$ts".tmp")

You are declaring an array variable, and you are quoting all the wrong parts. If anything, you need to quote the variables, not the constants. But you don't need to do that in a scalar assignment. You would have to in an array assignment using var=(...).
Quote:
oddly the loop works before I tried concatenating the string. variables are being read until I try to build the filename.

I have #!/bin/sh declared and no errors are being generated.

Then /bin/sh is not a Bourne shell.

The correct way to concatenate the variables is:
Code:
fnTmp=C$cindex.$sta_region.$sta_org.$sta_clientid.$ts.tmp

# 7  
Old 03-07-2010
thanks for the clarification. The () was me playing around trying to get it to output and I've tried the way you suggested previously with no success.

---------- Post updated at 02:22 AM ---------- Previous update was at 02:16 AM ----------

ahh i think I found the problem but not sure how to fix it...it's reading a confg file as per awk cmd but I think it's including the crlf.

---------- Post updated at 02:42 AM ---------- Previous update was at 02:22 AM ----------

humm adding the following fixed the problem:

Code:
# parse station parameters
set -- $(awk '/\['$cfgSec0']/{f=1;next}/\[/{f=0}f{print $NF}' $cfgFilePath)
#
staRegion=`echo $1 | sed 's/.$//'`
staOrg=`echo $2 | sed 's/.$//'`
staName=`echo $3 | sed 's/.$//'`
staClientId=`echo $4 | sed 's/.$//'`
staNetId=`echo $5 | sed 's/.$//'`

just not very clean per say
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