Depending upon what genre, period, and author one is examining, the way manhood is idealized changes.
For some authors, manhood is shown as aligning with the historically patriarchal man. What this means is that men are supposed to be the ones who work, in control of their wives, and function within the public sector (women exist within the private sector--home). Men are to take care of their families, financially. Men are to be proud, strong, and brave.
For other authors, the stereotype of the ideal man has changed. Men are no longer simply the bread winners. They are needed to help with the family (given their wives are working as well).
An example of a novel which epitomizes the classic view of a man is John Steinbeck's Of Mice and Men. The men portrayed in the novel are ranchers who worry about themselves and their "manhood." (This characterization is most seen in Curley.)
An example of a novel where the lines of the ideal man is crossed is William Faulkner's The Sound and the Fury. Here, Quentin Compson is weak, cannot function in society well, and ends up committing suicide. (He is not the picture of what the ideal man is.)