ref: 7b977c7290db3da3d6faa94606a8b7f1e7d39a1b dir: /sys/src/ape/lib/ap/plan9/execl.c/
#include <unistd.h> extern char **environ; int execl(const char *name, const char *arg0, ...) { return execve(name, &arg0, environ); }