mjhjmtu

#!/bin/bash

for (( x=7; x <= 65; x+=2 )) 

do


 if [ $x!=57 && $x!=59 && $x!=29 && $x!=53 ]
 then
 cd charged_$x 
 cp -f ~aman/user_ana_normal_mode/Testforaman/user_ana.so .
 cd ..
 fi

done

can't figure out the problem , please help

[ $x!=57 && $x!=59 && $x!=29 && $x!=53 ]

[ is a command, it obeys the same rules as, say ls. && is a shell way of conditionally grouping commands. In [ foo && bar ], the shell runs the command [ foo, and if it succeeds, it runs bar ]. The [ command fails because it expects to see a ] as its last argument, and so the second command does not run.

The special conditional syntax [[ .. ]] however does support && within it, so you could use [[ $x != 57 && $x != 59 && ... ]]. Note that it still requires whitespace around the operators. Plain $x!=57 would be a test to see if $x!=57 is a nonempty string, which it always is, regardless of the value of x.

Or, put the closing ] before the &&: [ "$x" != 57 ] && [ "$x" != 59 ] && ...

The following code should work:

#!/bin/bash

for (( x=7; x <= 65; x+=2 )) 
do
 if [ "$x" -ne 57 ] && [ "$x" -ne 59 ] && [ "$x" -ne 29 ] && [ "$x" -ne 53 ]; then
 cd charged_$x 
 cp -f ~aman/user_ana_normal_mode/Testforaman/user_ana.so .
 cd ..
 fi
done

• Its better to have separate braces for each condition.


• We should use -ne rather than !=, since we are comparing integers.

you use too many conditions at same time so you need to change syntax for that .

if [ $x!=57 ] && [ $x!=59 ] && [ $x!=29 ] && [ $x!=53 ]

this will work

Your code has two errors: The != operator needs spaces around it, and the && should be between individual [ ... ] tests.

Rather than using a lot of individual tests:

for (( x = 7; x <= 65; x += 2 )); do
 case $x in
 29|53|57|59) ;;
 *)
 cp -f ~aman/user_ana_normal_mode/Testforaman/user_ana.so "charged_$x"
 esac
done

I've also removed the half useless cd.