PHP Manual: Gets an exportable representation of a key into a file

Description

bool openssl_pkey_export_to_file(
    #[\SensitiveParameter]OpenSSLAsymmetricKeyOpenSSLCertificatearraystring $key,
    string $output_filename,
    #[\SensitiveParameter]stringnull $passphrase = null,
    arraynull $options = null
)

openssl_pkey_export_to_file saves an ascii-armoured (PEM encoded) rendition of key into the file named by output_filename.

Note: You need to have a valid openssl.cnf installed for this function to operate correctly. See the notes under the installation section for more information.

Parameters

key
output_filename: Path to the output file.
passphrase: The key can be optionally protected by a passphrase.
options: options can be used to fine-tune the export process by specifying and/or overriding options for the openssl configuration file. See openssl_csr_new for more information about options.

Return Values

Returns true on success or false on failure.

Changelog

Version	Description
8.0.0	`key` accepts an OpenSSLAsymmetricKey or OpenSSLCertificate instance now; previously, a resource of type `OpenSSL key` or `OpenSSL X.509` was accepted.