Why not SIGPIPE for readers of pipe/FIFO?

UNIX for Advanced & Expert Users
1

Hi

This is a exercise question from Unix network programming vol2.

Why the SIGPIPE signal is generated only for writers when readers disappear.
why not it is generated for readers when writer disappears.

I guess, if the writer didn't get any response like the reader gets EOF,
it will keep on adding bytes to pipe/FIFO and eventually cause PIPE_BUF to full.

Please correct me if i am wrong.

Thanks
Kumaran

2

See your book. Figure 4.21 contains the answer.

3

The figure 4.21 says that SIGPIPE will be generated to a write process, when the read process has been terminated/ no read process is present.

My doubt is why not the reader gets SIGPIPE when write process terminates/ no write process exists.

4

Think about it. Is reading still potentially possible when the writing process terminates?

5

Because there simply is no need to signal the reader as the reader already has a mechanism to detect this condition.