Print a character repeatedly in bash [duplicate]

Answer 1

1. It is possible to obtain any number of zero (\0) character from /dev/zero. The only thing left to do it is

   head -c 20 /dev/zero |tr '\0' '+'
   

   Note that head and tr are external commands. So that it would be invoked in separate process.

2. It is possible to "optimize" this solution with string caching.

   CACHE="$(head -c 1000 /dev/zero |tr '\0' '+')"
   echo "${CACHE:0:10}"
   echo "${CACHE:0:100}"
   echo "${CACHE:0:300}"
   

   There are only bash built-ins in the echo statement. So, we can use it in cycle.