ref: f6a6ccb1d56c0f6cf3677b6d7f31da0c8c362510 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); }