On Linux at least, execveat with a directory fd opened with O_CLOEXEC can't run programs that use #! such as shell scripts. So switch execvp back to allocating a buffer, using an mmap syscall so that it's safe to do in the child of a fork, and using plain execve.
On Linux at least,
execveatwith a directory fd opened withO_CLOEXECcan't run programs that use#!such as shell scripts. So switchexecvpback to allocating a buffer, using anmmapsyscall so that it's safe to do in the child of a fork, and using plainexecve.Also, implement
difftimeand__strncmp_chk.