Buzzy Linhart, a whimsically eccentric singer-songwriter and multi-instrumentalist whose compositions were recorded by Bette Midler, Carly Simon and others, died on Feb. 13 in Berkeley, Calif. He was 76.

His son Xeno Rasmusson confirmed the death. He said Mr. Linhart had been in declining health since having a heart attack in 2018.

The anthemic “(You Got to Have) Friends,” written by Mr. Linhart and Moogy Klingman, became Ms. Midler’s unofficial theme song after appearing in two versions on her debut album, “The Divine Miss M” (1972). It was also sung by Barry Manilow on his first album and, later, by the Muppets, in a duet with the actress Candice Bergen, and by Eddie Murphy’s donkey character in the hit animated feature film “Shrek.”

On his own, Mr. Linhart wrote the shimmering ballad “The Love’s Still Growing,” which closed Ms. Simon’s debut album, and which was subsequently recorded by the Roches for “Bleecker Street: Greenwich Village in the ’60s,” a 1999 album on which various artists performed songs from the 1960s Greenwich Village folk scene.