text: NAMEstrnlen - determine the length of a fixed-size string
  SYNOPSIS
  #include <string.h> size_t strnlen(const char *s, size_t maxlen);
  DESCRIPTIONThe strnlen function returns the number of characters in the string pointed to by s, not including the terminating '\0' character, but at most maxlen. In doing this, strnlen looks only at the first maxlen characters at s and never beyond s+maxlen.
  RETURN VALUEThe strnlen function returns strlen(s), if that is less than maxlen, or maxlen if there is no '\0' character among the first maxlen characters pointed to by s.
  CONFORMING TOThis function is a GNU extension.
  SEE ALSOstrlen(3)
  Important: Use the man command (% man) to see how a command is used on your particular computer.
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