PARIS — When France started shutting down a few weeks ago as the coronavirus marched relentlessly into the country, Dominique Paul feared disaster. His family’s white-glove catering company, Groupe Butard, halted operations, putting 190 jobs at risk.

Edward Arkwright, the director general of Aéroports de Paris, the Paris airport operator, weighed how to preserve over 140,000 jobs when a freeze on most global airline traffic caused activity to nose-dive 90 percent in a few head-spinning days.

The future of both businesses, and hundreds of thousands more around France, spiraled into uncertainty. Instead of sinking, though, they are being thrown lifelines as the French government deploys a targeted plan aimed at sheltering companies and keeping every worker possible employed.

“We’re using the government’s whole toolbox to get through this crisis,” Mr. Paul said, eyeing the company’s empty Armenonville Pavillon on the edge of Paris, where just weeks ago chefs and waiters served delicacies like scallop carpaccio for glittering events. “Otherwise, we wouldn’t be able to keep up.”