"Curtis is a proven NHL goaltender," Hurricanes president and general manager Don Waddell said in a statement. "Scott Darling is dealing with an injury and we see this as an opportunity to solidify our depth at the position."
Darling, who was 13-21-7 in 43 games (40 starts) for the Hurricanes last season, left Sunday's preseason game against the Nashville Predators with a lower-body injury. Coach Rod Brind'Amour told reporters on Tuesday that an MRI didn't reveal a major injury but that Darling will likely be out "a couple weeks, for sure.
"He looked good. I hate it for him. It's a setback no doubt, but that's why we got Petr (Mrazek)," Brind'Amour told reporters, according to the Raleigh News & Observer.
McElhinney, 35, was 11-5-1 in 18 games (15 starts) for the Maple Leafs last season.
The Hurricanes signed Mrazek in free agency. He played for the Philadelphia Flyers last season and went 6-6-3 in 17 games (15 starts).
Two other players were claimed Tuesday, hours before NHL teams were required to set their 23-player rosters.
Jaskin was the odd-man out after the Blues restocked their forwards this offseason. Jaskin was St. Louis' second-round pick in the 2011 draft and has 25 goals and 61 points in 266 games over six seasons.
The Buffalo Sabres claimed left wing Remi Elie from Dallas. The 23-year-old Elie was the Stars' second-round pick in the 2013 draft. He had six goals and 14 points in his first full season last year, and overall has seven goals and 21 points in 90 career NHL games.
Information from The Associated Press was used in this report.