added example

Author: wassup05

example/system/CMakeLists.txt

@@ -11,3 +11,4 @@ ADD_EXAMPLE(process_5)
 ADD_EXAMPLE(process_6)
 ADD_EXAMPLE(process_7)
 ADD_EXAMPLE(sleep)
+ADD_EXAMPLE(fs_error)

example/system/example_fs_error.f90

@@ -0,0 +1,23 @@
+! Demonstrate usage of `fs_error`, `fs_error_code`
+program example_fs_error
+    use stdlib_system, only: fs_error, fs_error_code
+    use stdlib_error, only: state_type, STDLIB_FS_ERROR
+    implicit none
+
+    type(state_type) :: err0, err1
+
+    err0 = fs_error("Could not create directory", "`temp.dir`", "- Already exists")
+
+    if (err0%state == STDLIB_FS_ERROR) then
+        ! Error encountered: Filesystem Error: Could not create directory `temp.dir` - Already exists
+        print *, err0%print() 
+    end if
+
+    err1 = fs_error_code(1, "Could not create directory", "`temp.dir`", "- Already exists")
+
+    if (err1%state == STDLIB_FS_ERROR) then
+        ! Error encountered: Filesystem Error: code - 1, Could not create directory `temp.dir` - Already exists
+        print *, err1%print()
+    end if
+
+end program example_fs_error