一
[jean@jeantoe /]$ command -v ls >/dev/null && echo “command Found In \$PATH” || echo “command Not Found in \$PATH”
command1 Found In $PATH
[jean@jeantoe /]$ command -v ss >/dev/null && echo “command Found In \$PATH” || echo “command Not Found in \$PATH”
command Found In $PATH
二
[jean@jeantoe /]$ type -P command1 &>/dev/null && echo “Found” || echo “Not Found”
Not Found
