```{index} single: asctime; POSIX function ``` ```{index} single: POSIX::asctime; Perl function ``` # asctime Canonical English timestamp string from a broken-down time. ## Synopsis ```perl use POSIX qw(asctime); my @tm = localtime; print asctime(@tm); # "Wed Apr 22 14:30:00 2026\n" ``` ## What you get back A 25-byte string **including the trailing newline**, or `undef` if nine arguments are not supplied. ## Differences from upstream Fully compatible with upstream POSIX. The trailing newline is preserved as-is; do not assume this function trims it.