Example of waiting for a typical shell prompt on console object $con:
bp.console_string.trace $con "~ $"
If -regexp is specified, the breakpoint string will be interpreted as a regular expression (regexp). The regexp syntax follows the common Perl style, as interpreted by the Hyperscan library https://hyperscan.io.
Note that the string is a Simics CLI string, and thus \ has to be escaped as \\ when writing the regexp.
Examples:
$con.bp-trace-string -regexp "\\d{3}"
$con.bp-trace-string -regexp "\\[.*4.*\\]"
$con.bp-trace-string -regexp "\\w{3}|[{}]{6}"
For more information about regular expression syntax, see https://perldoc.perl.org/re.html.