#A4# #pipe buffer (4096)# #kernel# #stdout buffer (4096)# #write()# #tail -f access.log# #stdin buffer (4096)# #read()# #fgets()# #cut -d' ' -f1# #fwrite()# #libc# #libc# #pipe buffer (4096)# #stdout buffer (4096)# #write()# #fwrite()# #stdin buffer (4096)# #read()# #fgets()# #uniq# #libc# #stdout buffer (line, 1024)# #fwrite()# #write()# ## #read()#