Along with the “&&” (and) expression, I also like to use the the “OR” expression to manage error cases. For example this usage:

statement1 || or-statement

This will cause the “or-statement” to run if the “statement1″ command fails (ie, exits non-zero).

One can combine the “OR” and “AND” expressions with code blocks for a short hand if/then/else syntax

statement1 &|| {
else-statement1; else-statement2
}

Here’s a concrete example that checks if an error string is found in a log file

grep ERROR /path/to/log &|| {
echo “error found on `hostname`:/path/log/log|mail -s “error detected”
exit 1
}