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Für diese Funktionen ist keine Installation erforderlich, diese gehören zum Grundbestand von PHP.
Installation steps on CentOs 5.3 include
# yum install php-devel
# yum install php-pear
# yum install gcc
# pear install pecl/json
# cd /etc/php.d
# echo "extension=json.so" > json.ini
# service httpd restart
After that phpinfo() would output
json support enabled
json version 1.2.1
On one server I use (FreeBSD 6.3; PHP 5.2.6 as module in Apache 2.2.10), PHP was compiled with the '--disable-all' configuration option. Consequently, there exists a secondary configuration file -- /usr/local/php5/etc/extensions.ini -- in which the line
; extension=json.so
must be uncommented (delete the semicolon) and Apache restarted for these functions to be available.
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