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where's the bug?

 
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# 1  
Old 08-31-2008
where's the bug?
#!/bin/bash
if [1 eq 1] then
#echo "infinite loop"
exit 0
fi

when I run this file I get the following error:
./test_infinite_loop: line 5: syntax error near unexpected token `fi'
./test_infinite_loop: line 5: `fi'

Smilie
# 2  
Old 08-31-2008
Code:
#  if [ 1 -eq 1 ];
More >then
More >echo hello
More >fi
hello

# 3  
Old 08-31-2008
Quote:
Originally Posted by jon80
if [1 eq 1] then
You need to have spaces inside the square brackets; [ is the name of a command so it needs to be a separate token, and it looks for a lone closing ] token.
# 4  
Old 08-31-2008
Quote:
Originally Posted by era
You need to have spaces inside the square brackets; [ is the name of a command so it needs to be a separate token, and it looks for a lone closing ] token.
hmm...thanks, but it still does not work Smilie
# 5  
Old 08-31-2008
Actually you also need a dash before the option -eq.

Anyway, the conventional way to code an endless loop is

Code:
while true; do
  : nothing
done

Sometimes you see the shell's built in "noop" command, the colon (:), in place of true (which I coincidentally used in the loop's body, before the "nothing" comment).

The if is a conditional, not a loop.

Code:
if true; then
  : always do this once
else
  : never do this
fi

 
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