functions and variables in bash

Shell Programming and Scripting
1

I have a bash script with some functions as below and am wondering if I can use the variables declared in setup in the other functions and in the rest of the bash script.

setup(){

  none=0; low=1; medium=2; high=3; debug=4

  var1="red"
  var2="fred"

}

create_basemap() {
   
 xminBse=$(( $xmin - 2.0 ))   
 xmaxBse=$(( $xmax + 2.0 ))   
 zminBse=$(( $zmin - 2.0 ))     
 zmaxBse=$(( $zmax + 2.0 )) 
  
 xpos=0   
 ypos=0   
 xpos=$xmin   
 ypos=$(( $zmax + 1.5 ))   
 title="Sound speed, c, Mm/min"   
 xDesc="Distance, x, Mm"   
 yDesc="Depth, z, Mm" 
  
 # Scale attributes   xpos=$(( $wtimap + 0.5 ))    
 ypos=$(( $htimap / 2.0 ))   
 sclen=$htimap   scwid=0.4   

 # Create the grid   
 xyz2grd $f.xzc -G$f.grd -I$vdx/$vdz -R$xmin/$xmax/$zmin/$zmax   # Create the color palette   makecpt -C$color -T$cmin/$cmax/0.005 -Z > $f.cpt   

 # Create the basemap    
 wtbmap=$(( $wtimap + 6 ))   
 htbmap=$(( $htimap + 5 ))   
 psbasemap -JX$wtbmap/$htbmap -R0/$wtbmap/0/$htbmap -B0 -K > $f.ps
}

create_contour() {
                           
 textPosx=`echo $xminBse | awk '{print $1 + 1.2}'`   
 textPosy=`echo $zmaxBse | awk '{print $1 - 1.2}'`   
 txt="$textPosx $textPosy 12 0.0 0 BL $fullname"   
 echo $txt | pstext -JX$wtbmap/$htbmap -R$xminBse/$xmaxBse/$zminBse/$zmaxBse -Wwhite -O -K >> $f.ps   
 # Display the image    
 grdimage $f.grd -JX$wtimap/$htimap -R$xmin/$xmax/$zmin/$zmax -C$f.cpt  -B$ax:"$xDesc":/$az:"$yDesc"::."$title":WSne -X2.5 -Y2 -O -K >> $f.ps   

 # Can use units on the contours if needed   
 units="Mm/min"   
 units=""   

 # Annotate contour lines every ${labeldistx} cm   
 contLabelDist=`echo $wtimap | awk '{print $1/2}'`   
 contLabelDist="d${contLabelDist}c"   

 # Include contour lines with annotations   
 grdcontour $f.grd -C$ctc -JX -A$cta+v+u$units -G$contLabelDist -B -R -O -K >> $f.ps  

}
2

Yes you can, as long as you don't use "local" for the variables (and of course if you call "setup" before other uses of the variable).

3

That's good. So now I consider the following toy problem. I have two bash scripts as follows

cat colors.bash

#!/bin/bash  

colors() {   
  red="red"  
  blue="blue"   
  green="green" 
} 

car() {
  color_car="$red"
} 

pen() {
  pen_color="$blue"
}

cat property.bash  

source colors.bash  
my_property() {
  echo "$color_car"
}

I want to have the function my_property returning red. My problem is that I do not want to call the function colors inside car before setting

color_car="$red"
4

Don't call that function, then.

5

Ok, so I just call colors in my_property, which seems to work

source colors.bash  
my_property() {
  colors
  car
  echo $color_car
 }

---------- Post updated at 04:53 PM ---------- Previous update was at 04:44 PM ----------

My problem is this:

Suppose I have lots of properties which all call colors

pen
car
box
ball
plate

and then I start calling pen and car several times in my_property, this would mean that all colors would be redefined everytime which is a waste

Here is an example

cat colors.bash

#!/bin/bash  

colors() {   
  red="red"  
  blue="blue"   
  green="green" 
} 

car() {
  echo $red
} 

pen() {
   echo $blue
}

ball() {
    echo $blue
 }
 
plate() {
   echo $blue
  }
  

cat property.bash

#!/bin/bash  

my_property() {
  colors

  car
  car
  car
  plate
  echo $red
 
}
6

As the last line in colors.bash you can call the function colors.

7

Even if the functions are declared before calling colors?

8

Yes, the code in the functions are not executed when declaring them.