Bash while loop error -

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• why should there space after '[' , before ']' in bash? 4 answers

this simple school project. console keeps stating [5:command not found

#!/bin/bash  num=28 echo "guess number number between 1 , 100" read guess  while [$guess -ne $num]   if [$guess -lt $num]       echo "number higher"  elif [$guess -gt $num]       echo "number lower"   else      echo "correct! number $number"   fi  done 

while [$guess -ne $num] 

is interpreted first expanding parameters:

while [5 -ne 28] 

which causes command [5 executed, passing arguments -ne , 28]

you wanted execute command [, needed write:

while [ $guess -ne $num ] 

(note spaces around both [ , ]. without space, characters become part of word.)

ditto statements following if , elif.