pub fn search_defpath(cmd: &str, plen: usize) -> Option<String>Expand description
Port of static char *search_defpath(char *cmd, char *pbuf, int plen)
from Src/exec.c:691.
Walk DEFAULT_PATH for an executable <dir>/<cmd> regular file.
Used by command -p to bypass the user’s $PATH and search the
system default (/bin:/usr/bin:...).