for ((i=0; i<10; i++)) do echo "$i" done
i=0 while [ "$i" -lt 10 ] do echo "$i" i=$((i+1)) done
C-style arithmetic for loops are a Ksh/Bash feature that's not supported by POSIX sh or dash. Use a
while loop with separate initialization and incrementing instead.
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.