ref: 6cd562fb445e1bd0fbae9837ab6c7d0f9a0bb6ce dir: /sys/src/libc/port/needsrcquote.c/
#include <u.h> #include <libc.h> int needsrcquote(int c) { if(c <= ' ') return 1; if(utfrune("`^#*[]=|\\?${}()'<>&;", c)) return 1; return 0; }