strace Use Example - The Networked Client (Cont.)

We now open the '/etc/host.conf' file - to know how to perform host name lookup:

open("/etc/host.conf", O_RDONLY)        = 3
fstat64(3, {st_mode=S_IFREG|0644, st_size=17, ...}) = 0
old_mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40013000
read(3, "order hosts,bind\n", 4096)     = 17
read(3, "", 4096)                       = 0
close(3)                                = 0
munmap(0x40013000, 4096)                = 0

We were told to consult '/etc/hosts' first (see the 'read' above) - lets do that:

open("/etc/hosts", O_RDONLY)            = 3
fcntl64(3, F_GETFD)                     = 0
fcntl64(3, F_SETFD, FD_CLOEXEC)         = 0
fstat64(3, {st_mode=S_IFREG|0644, st_size=230, ...}) = 0
old_mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40013000
read(3, "127.0.0.1\t\tlocalhost\n204.141.72."..., 4096) = 230
read(3, "", 4096)                       = 0
close(3)                                = 0
munmap(0x40013000, 4096)                = 0