In PHP 5 there are some new functions. Here is the list of them:
array_combine() - Creates an array by using one array for keys and another for its values
array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
array_udiff() - Computes the difference of arrays by using a callback function for data comparison
array_udiff_assoc() - Computes the difference of arrays with additional index check. The data is compared by using a callback function
array_udiff_uassoc() - Computes the difference of arrays with additional index check. The data is compared by using a callback function. The index check is done by a callback function also
array_walk_recursive() - Apply a user function recursively to every member of an array
array_uintersect_assoc() - Computes the intersection of arrays with additional index check. The data is compared by using a callback function
array_uintersect_uassoc() - Computes the intersection of arrays with additional index check. Both the data and the indexes are compared by using a callback functions
array_uintersect() - Computes the intersection of arrays. The data is compared by using a callback function
ibase_affected_rows() - Return the number of rows that were affected by the previous query
ibase_backup() - Initiates a backup task in the service manager and returns immediately
ibase_commit_ret() - Commit a transaction without closing it
ibase_db_info() - Request statistics about a database
ibase_drop_db() - Drops a database
ibase_errcode() - Return an error code
ibase_free_event_handler() - Cancels a registered event handler
ibase_gen_id() - Increments the named generator and returns its new value
ibase_maintain_db() - Execute a maintenance command on the database server
ibase_name_result() - Assigns a name to a result set
ibase_num_params() - Return the number of parameters in a prepared query
ibase_param_info() - Return information about a parameter in a prepared query
ibase_restore() - Initiates a restore task in the service manager and returns immediately
ibase_rollback_ret() - Rollback transaction and retain the transaction context
ibase_server_info() - Request statistics about a database
ibase_service_attach() - Connect to the service manager
ibase_service_detach() - Disconnect from the service manager
ibase_set_event_handler() - Register a callback function to be called when events are posted
ibase_wait_event() - Wait for an event to be posted by the database
iconv_mime_decode() - Decodes a MIME header field
iconv_mime_decode_headers() - Decodes multiple MIME header fields at once
iconv_mime_encode() - Composes a MIME header field
iconv_strlen() - Returns the character count of string
iconv_strpos() - Finds position of first occurrence of a needle within a haystack
iconv_strrpos() - Finds the last occurrence of a needle within the specified range of haystack
iconv_substr() - Cut out part of a string
stream_copy_to_stream() - Copies data from one stream to another
stream_get_line() - Gets line from stream resource up to a given delimiter
stream_socket_accept() - Accept a connection on a socket created by stream_socket_server()
stream_socket_client() - Open Internet or Unix domain socket connection
stream_socket_get_name() - Retrieve the name of the local or remote sockets
stream_socket_recvfrom() - Receives data from a socket, connected or not
stream_socket_sendto() - Sends a message to a socket, whether it is connected or not
stream_socket_server() - Create an Internet or Unix domain server socket
idate() - Format a local time/date as integer
date_sunset() - Time of sunset for a given day and location
date_sunrise() - Time of sunrise for a given day and location
time_nanosleep() - Delay for a number of seconds and nano seconds
str_split() - Convert a string to an array
strpbrk() - Search a string for any of a set of characters
substr_compare() - Binary safe optionally case insensitive comparison of two strings from an offset, up to length characters
Other:
convert_uudecode() - decode a uuencoded string
convert_uuencode() - uuencode a string
curl_copy_handle() - Copy a cURL handle along with all of it's preferences
dba_key_split() - Splits a key in string representation into array representation
dbase_get_header_info() - Get the header info of a dBase database
dbx_fetch_row() - Fetches rows from a query-result that had the DBX_RESULT_UNBUFFERED flag set
fbsql_set_password() - Change the password for a given user
file_put_contents() - Write a string to a file
ftp_alloc() - Allocates space for a file to be uploaded
get_declared_interfaces() - Returns an array of all declared interfaces
get_headers() - Fetches all the headers sent by the server in response to a HTTP request
headers_list() - Returns a list of response headers sent (or ready to send)
http_build_query() - Generate URL-encoded query string
image_type_to_extension() - Get file extension for image-type returned by getimagesize(), exif_read_data(), exif_thumbnail(), exif_imagetype()
imagefilter() - Applies Filter an image using a custom angle
imap_getacl() - Gets the ACL for a given mailbox
ldap_sasl_bind() - Bind to LDAP directory using SASL
mb_list_encodings() - Returns an array of all supported encodings
pcntl_getpriority() - Get the priority of any process
pcntl_wait() - Waits on or returns the status of a forked child as defined by the waitpid() system call
pg_version() - Returns an array with client, protocol and server version (when available)
php_check_syntax() - Check the syntax of the specified file
php_strip_whitespace() - Return source with stripped comments and whitespace
proc_nice() - Change the priority of the current process
pspell_config_data_dir() - Change location of language data files
pspell_config_dict_dir() - Change location of the main word list
setrawcookie() - Send a cookie with no url encoding of the value
snmp_read_mib() - Reads and parses a MIB file into the active MIB tree
sqlite_fetch_column_types() - Return an array of column types from a particular table
Note: The Tidy extension has also changed its API completely.