Filename	/usr/lib/perl/5.10/Sys/Hostname.pm
Statements	Executed 20 statements in 881µs

Subroutines

Calls	P	F	Exclusive Time	Inclusive Time	Subroutine
1	1	1	24µs	203µs	Sys::Hostname::::BEGIN@17Sys::Hostname::BEGIN@17
1	1	1	16µs	20µs	Sys::Hostname::::BEGIN@3Sys::Hostname::BEGIN@3
1	1	1	11µs	57µs	Sys::Hostname::::BEGIN@5Sys::Hostname::BEGIN@5
0	0	0	0s	0s	Sys::Hostname::::hostnameSys::Hostname::hostname

Call graph for these subroutines as a Graphviz dot language file.

Line	State ments	Time on line	Calls	Time in subs	Code
1					package Sys::Hostname;
2
3	3	27µs	2	25µs	# spent 20µs (16+4) within Sys::Hostname::BEGIN@3 which was called: # once (16µs+4µs) by Mail::Sendmail::BEGIN@56 at line 3 use strict; # spent 20µs making 1 call to Sys::Hostname::BEGIN@3 # spent 4µs making 1 call to strict::import
4
5	3	128µs	2	104µs	# spent 57µs (11+46) within Sys::Hostname::BEGIN@5 which was called: # once (11µs+46µs) by Mail::Sendmail::BEGIN@56 at line 5 use Carp; # spent 57µs making 1 call to Sys::Hostname::BEGIN@5 # spent 46µs making 1 call to Exporter::import
6
7	1	1µs			require Exporter;
8	1	900ns			require AutoLoader;
9
10	1	14µs			our @ISA = qw/ Exporter AutoLoader /;
11	1	700ns			our @EXPORT = qw/ hostname /;
12
13	1	200ns			our $VERSION;
14
15	1	100ns			our $host;
16
17					# spent 203µs (24+179) within Sys::Hostname::BEGIN@17 which was called: # once (24µs+179µs) by Mail::Sendmail::BEGIN@56 at line 27 BEGIN {
18	2	5µs			$VERSION = '1.11';
19					{
20	3	8µs			local $SIG{__DIE__};
21	2	187µs			eval {
22					require XSLoader;
23			1	180µs	XSLoader::load('Sys::Hostname', $VERSION); # spent 180µs making 1 call to XSLoader::load
24					};
25					warn $@ if $@;
26					}
27	1	502µs	1	203µs	} # spent 203µs making 1 call to Sys::Hostname::BEGIN@17
28
29
30					sub hostname {
31
32					# method 1 - we already know it
33					return $host if defined $host;
34
35					# method 1' - try to ask the system
36					$host = ghname() if defined &ghname;
37					return $host if defined $host;
38
39					if ($^O eq 'VMS') {
40
41					# method 2 - no sockets ==> return DECnet node name
42					eval { local $SIG{__DIE__}; $host = (gethostbyname('me'))[0] };
43					if ($@) { return $host = $ENV{'SYS$NODE'}; }
44
45					# method 3 - has someone else done the job already? It's common for the
46					# TCP/IP stack to advertise the hostname via a logical name. (Are
47					# there any other logicals which TCP/IP stacks use for the host name?)
48					$host = $ENV{'ARPANET_HOST_NAME'} || $ENV{'INTERNET_HOST_NAME'} ||
49					$ENV{'MULTINET_HOST_NAME'} || $ENV{'UCX$INET_HOST'} ||
50					$ENV{'TCPWARE_DOMAINNAME'} || $ENV{'NEWS_ADDRESS'};
51					return $host if $host;
52
53					# method 4 - does hostname happen to work?
54					my($rslt) = `hostname`;
55					if ($rslt !~ /IVVERB/) { ($host) = $rslt =~ /^(\S+)/; }
56					return $host if $host;
57
58					# rats!
59					$host = '';
60					croak "Cannot get host name of local machine";
61
62					}
63					elsif ($^O eq 'MSWin32') {
64					($host) = gethostbyname('localhost');
65					chomp($host = `hostname 2> NUL`) unless defined $host;
66					return $host;
67					}
68					elsif ($^O eq 'epoc') {
69					$host = 'localhost';
70					return $host;
71					}
72					else { # Unix
73					# is anyone going to make it here?
74
75					local $ENV{PATH} = '/usr/bin:/bin:/usr/sbin:/sbin'; # Paranoia.
76
77					# method 2 - syscall is preferred since it avoids tainting problems
78					# XXX: is it such a good idea to return hostname untainted?
79					eval {
80					local $SIG{__DIE__};
81					require "syscall.ph";
82					$host = "\0" x 65; ## preload scalar
83					syscall(&SYS_gethostname, $host, 65) == 0;
84					}
85
86					# method 2a - syscall using systeminfo instead of gethostname
87					# -- needed on systems like Solaris
88					|| eval {
89					local $SIG{__DIE__};
90					require "sys/syscall.ph";
91					require "sys/systeminfo.ph";
92					$host = "\0" x 65; ## preload scalar
93					syscall(&SYS_systeminfo, &SI_HOSTNAME, $host, 65) != -1;
94					}
95
96					# method 3 - trusty old hostname command
97					|| eval {
98					local $SIG{__DIE__};
99					local $SIG{CHLD};
100					$host = `(hostname) 2>/dev/null`; # bsdish
101					}
102
103					# method 4 - use POSIX::uname(), which strictly can't be expected to be
104					# correct
105					|| eval {
106					local $SIG{__DIE__};
107					require POSIX;
108					$host = (POSIX::uname())[1];
109					}
110
111					# method 5 - sysV uname command (may truncate)
112					|| eval {
113					local $SIG{__DIE__};
114					$host = `uname -n 2>/dev/null`; ## sysVish
115					}
116
117					# method 6 - Apollo pre-SR10
118					|| eval {
119					local $SIG{__DIE__};
120					my($a,$b,$c,$d);
121					($host,$a,$b,$c,$d)=split(/[:\. ]/,`/com/host`,6);
122					}
123
124					# bummer
125					|| croak "Cannot get host name of local machine";
126
127					# remove garbage
128					$host =~ tr/\0\r\n//d;
129					$host;
130					}
131					}
132
133	1	5µs			1;
134
135					__END__