3v4l.org

run code in 300+ PHP versions simultaneously
<?php ini_set('session.name', ''); var_dump(session_name("foo"));
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Warning: ini_set(): session.name "" cannot be numeric or empty in /in/r4YSU on line 3 Warning: session_name(): Session name cannot be changed after headers have already been sent in /in/r4YSU on line 5 bool(false)
Output for 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: ini_set(): session.name cannot be a numeric or empty '' in /in/r4YSU on line 3 Warning: session_name(): Cannot change session name when headers already sent in /in/r4YSU on line 5 bool(false)
Output for 5.4.18 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33
Warning: ini_set(): session.name cannot be a numeric or empty '' in /in/r4YSU on line 3 string(9) "PHPSESSID"
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.17
string(0) ""

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