Shell Programming and Scripting

      if [ $_CHAR -eq $_CHAR 2>/dev/null ]; then
         _VALUE=$_VALUE$_CHAR
      else
         _ISDIGIT="false"
      fi

      if [[ $_CHAR -eq $_CHAR 2>/dev/null || $_CHAR == "*" ]]; then
         _VALUE=$_VALUE$_CHAR
      else
         _ISDIGIT="false"
      fi

./statusSIGTRAN_TSP5.sh: line 35: syntax error in conditional expression
./statusSIGTRAN_TSP5.sh: line 35: syntax error near `2>'
./statusSIGTRAN_TSP5.sh: line 35: `      if [[ $_CHAR -eq $_CHAR 2>/dev/null || $_CHAR == "*" ]]; then'

#!/bin/ksh
isdigit()
{
		case "$1" in
		  ?(1|2|3|4|5|6|7|8|9|0)) ok=1;;
		  *) ok=0;;
		esac
		echo $ok 
} 

for i in 1 2 3 4 a d
do
  echo "isdigit $i returns $(isdigit $i)"
done

 
if [ $_CHAR -eq $_CHAR ]; then
 
./test.sh: line 23: [: -: integer expression expected
34622991111
./test.sh: line 23: [: -: integer expression expected
34622991211
./test.sh: line 23: [: -: integer expression expected
34622999213
./test.sh: line 23: [: too many arguments

      if [$_CHAR == "*" ]; then
         _VALUE=$_VALUE$_CHAR
      else
         _ISDIGIT="false"
      fi

./test.sh: line 23: [3: command not found
./test.sh: line 23: [3: command not found
./test.sh: line 23: [3: command not found
./test.sh: line 23: [*: command not found