 Literary wisdom has it that you write what you know, and one detects a heartfelt conviction in Roddy Doyle's insightful collection of stories that for a man of a certain age - and, like the author himself, all his protagonists are men of a certain age - nothing is more keenly known than what one of them calls "death becoming real". It's a complaint about "getting older, slower, tired, bored, useless", but it adds up to a creeping mortality that casts a shadow on every page.  This is midlife crisis painted as an awakening - that is, an awakening to something more than the desire for a younger woman or an earring or an electric guitar. It is the less mocked world of illness, empty nests, parental regret, marriages and family life drifting into entropy. The names change but Doyle's men of the "manopause" bend in the same direction, their worried heads blowing in the wind like dandelion clocks.  There's some irony at play. In "Teaching", a lonely teacher, his opportunities for a more fruitful life squandered, urges his pupils to seize the day; in "Recuperation", a lonely convalescent pounding the streets for the good of his health can summon thoughts only of the vanished past. Everywhere you look is a double edge. The unemployed stand for Ireland's economic ruin but also for their dwindling usefulness as husbands and fathers; a man reduced to skin and bone by cancer is mirrored by a friend shrunken in worth after years of pandering to kids who no longer need him.  all but one of the stories have appeared singly elsewhere - mostly in the New Yorker - but here they give the impression of being related to one another, or at least of having come to the same funeral. It can get a bit gloomy. There's more than one tunnel of interior monologue to get through, and there are moments when Doyle's trademark deadpan, unadorned prose seems unsuited to its constraints, its flatness if anything drawing attention to its subject's grim sameness of tone.  He succeeds more convincingly when he has his characters bounce off one another to produce the rolling, demotic blarney and craic of his early, funny novels with their triumphant highs and maudlin lows. The best and most vividly drawn is the title story - about a group o 