PHP Function Reference

PHP - Network

The PHP provides contains various network functions which let you manipulate information sent to the browser by the Web server, before any other output has been sent.


There is no installation needed to use these functions. These functions are part of the PHP core.

Runtime Configuration

This extension has no configuration directives defined in php.ini.

PHP Network Functions

checkdnsrr() Check DNS records corresponding to a given Internet host name or IP address.
closelog() Closes connection to system logger.
dns_check_record() Check DNS records corresponding to a given Internet host name or IP address. Alias of checkdnsrr() function.
dns_get_record() Fetch DNS Resource Records associated with a hostname.
dns_get_mx() Get MX records corresponding to a given Internet host name. Alias of getmxrr() function.
fsockopen() Open Internet or Unix domain socket connection.
gethostname() Gets the host name.
gethostbyaddr() Get the Internet host name corresponding to a given IP address.
gethostbyname() Get the IPv4 address corresponding to a given Internet host name.
gethostbynamel() Get a list of IPv4 addresses corresponding to a given Internet host name.
getmxrr() Get MX records corresponding to a given Internet host name.
getprotobyname() Get protocol number associated with protocol name.
getprotobynumber() Get protocol name associated with protocol number.
getservbyname() Get port number associated with an Internet service and protocol.
getservbyport() Get Internet service which corresponds to port and protocol.
header_register_callback() Call a header function.
header_remove() Remove previously set headers.
header() Sends a raw HTTP header.
headers_list() Returns a list of response headers sent (or ready to send).
headers_sent() Checks if or where headers have been sent.
http_response_code() Gets or Sets the HTTP response code.
inet_ntop() Converts a packed internet address to a human readable representation.
inet_pton() Converts a human readable IP address to its packed in_addr representation.
ip2long() Converts a string containing an (IPv4) Internet Protocol dotted address into a long integer.
long2ip() Converts an long integer address into a string in (IPv4) Internet standard dotted format.
openlog() Opens connection to system logger.
pfsockopen() Open persistent Internet or Unix domain socket connection.
setcookie() Send a cookie.
setrawcookie() Send a cookie without urlencoding the cookie value.
socket_get_status() Retrieves header/meta data from streams/file pointers. Alias of stream_get_meta_data() function.
socket_set_blocking() Set blocking/non-blocking mode on a stream. Alias of stream_set_blocking() function.
socket_set_timeout() Set timeout period on a stream. Alias of stream_set_timeout() function.
syslog() Generates a system log message.

PHP Network Predefined Constants

The constants below are always available as part of the PHP core.

openlog() Options

LOG_CONSif there is an error while sending data to the system logger, write directly to the system console
LOG_NDELAY open the connection to the logger immediately
LOG_ODELAY (default) delay opening the connection until the first message is logged
LOG_PERROR print log message also to standard error
LOG_PID include PID with each message

openlog() Facilities

LOG_AUTH security/authorization messages (use LOG_AUTHPRIV instead in systems where that constant is defined)
LOG_AUTHPRIV security/authorization messages (private)
LOG_CRON clock daemon (cron and at)
LOG_DAEMON other system daemons
LOG_KERN kernel messages
LOG_LOCAL0 ... LOG_LOCAL7 reserved for local use, these are not available in Windows
LOG_LPR line printer subsystem
LOG_MAIL mail subsystem
LOG_NEWS USENET news subsystem
LOG_SYSLOG messages generated internally by syslogd
LOG_USER generic user-level messages
LOG_UUCP UUCP subsystem

syslog() Priorities (in descending order)

LOG_EMERG system is unusable
LOG_ALERT action must be taken immediately
LOG_CRIT critical conditions
LOG_ERR error conditions
LOG_WARNING warning conditions
LOG_NOTICE normal, but significant, condition
LOG_INFO informational message
LOG_DEBUG debug-level message

dns_get_record() Options

DNS_AIPv4 Address Resource
DNS_CAA Certification Authority Authorization Resource (available as of PHP 7.0.16 and 7.1.2)
DNS_MX Mail Exchanger Resource
DNS_CNAME Alias (Canonical Name) Resource
DNS_NS Authoritative Name Server Resource
DNS_PTR Pointer Resource
DNS_HINFO Host Info Resource
DNS_SOA Start of Authority Resource
DNS_TXT Text Resource
DNS_ANY Any Resource Record. On most systems this returns all resource records, however it should not be counted upon for critical uses. Try DNS_ALL instead.
DNS_AAAA IPv6 Address Resource
DNS_ALL Iteratively query the name server for each available record type.