Linker error while compiling using CLI

Firmware
16

If you only want to read the suffix, you won’t need to unlock the flash, you can just read that address direct.

This is a simple sketch that demonstrates that

uint8_t *s1 = (uint8_t*)0x80064B8;
uint8_t *s2 = (uint8_t*)0x800A4B8;
char    suffix1[8];
char    suffix2[8];

void setup() {
    Particle.function("setSuffix", setSuffix);
}

int setSuffix(String arg) {
  String suffix = arg.substring(0,6);
  
  memset(suffix1, 0, sizeof(suffix1));
  memcpy(suffix1, s1, sizeof(suffix1)-1);

  memset(suffix2, 0, sizeof(suffix2));
  memcpy(suffix2, s2, sizeof(suffix2)-1);
  Serial.printlnf("Before: 0x%08X: %6s\r\n        0x%08X: %6s", (uint32_t)s1, suffix1, (uint32_t)s2, suffix2);


  System.set(SYSTEM_CONFIG_SOFTAP_SUFFIX, arg.substring(0,6));

  memset(suffix1, 0, sizeof(suffix1));
  memcpy(suffix1, s1, suffix.length());

  memset(suffix2, 0, sizeof(suffix2));
  memcpy(suffix2, s2, suffix.length());
  Serial.printlnf("After : 0x%08X: %6s\r\n        0x%08X: %6s", (uint32_t)s1, suffix1, (uint32_t)s2, suffix2);

  return suffix.length();
}

You can set a new suffix and will get the suffix stored in the two locations before and after the change as serial output.