This function returns a positive ID on success; zero on failure.
yaz_connect() prepares for a connection to a Z39.50 target. The zurl argument takes the form host[:port][/database]. If port is omitted 210 is used. If database is omitted Default is used. This function is non-blocking and doesn't attempt to establish a socket - it merely prepares a connect to be performed later when yaz_wait() is called.
If the second argument, options, is given as a string it is treated as the Z39.50 V2 authentication string (OpenAuth).
If options is given as an array the contents of the array serves as options. Note that array options are only supported for PHP 4.1.0 and later.
Username for authentication.
Group for authentication.
Password for authentication.
Cookie for session (YAZ proxy).
Proxy for connection (YAZ proxy).
A boolean. If TRUE the connection is persistent; If FALSE the connection is not persistent. By default connections are persistent.
A boolean. If TRUE piggyback is enabled for searches; If FALSE piggyback is disabled. By default piggyback is enabled. Enabling piggyback is more efficient and usually saves a network-round-trip for first time fetches of records. However, a few Z39.50 targets doesn't support piggyback or they ignore element set names. For those, piggyback should be disabled.