gnu: Add julia-pidfile.

* gnu/packages/julia-xyz.scm (julia-pidfile-1.1.0): New variable.

gnu/packages/julia-xyz.scm

@@ -1017,3 +1017,27 @@ dependencies (and long load times) can be avoided.")
 WebSockets is a small overhead message protocol layered over TCP.  It uses
 HTTP(S) for establishing the connections.")
     (license license:expat)))
+
+(define-public julia-pidfile
+  (package
+    (name "julia-pidfile")
+    (version "1.1.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri
+        (git-reference
+         (url "https://github.com/vtjnash/Pidfile.jl")
+         ;; Project.toml added after 1.1.0 release
+         (commit "b7c9060ad7fc57c9c1341d8a87392e25580b6b71")))
+       (file-name "Pidfile")
+       (sha256
+        (base32 "11pml7ls8dsipbcmngsqgdfwsdza9xjmy1974i5kiik7skhv860x"))))
+    (propagated-inputs
+     `(("julia-compat" ,julia-compat)))
+    (build-system julia-build-system)
+    (home-page "https://vtjnash.github.io/Pidfile.jl/")
+    (synopsis "Utility for creating advisory pidfiles (lock files)")
+    (description "Simple utility tool for creating advisory pidfiles (lock
+files).")
+    (license license:expat)))