ref: bf4f158707ebfeacb15826ad4283ff247d7d81ae 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; }