#!/bin/bash # seeding-random.sh: RANDOM º¯¼ö¿¡ seed Àû¿ë. MAXCOUNT=25 # ¹ß»ý½Ãų ¼ýÀÚ °¹¼ö. random_numbers () { count=0 while [ "$count" -lt "$MAXCOUNT" ] do number=$RANDOM echo -n "$number " let "count += 1" done } echo; echo RANDOM=1 # ·£´ý ³Ñ¹ö ¹ß»ý±â¿¡ RANDOM seed ¼¼ÆÃ. random_numbers echo; echo RANDOM=1 # ¶È°°Àº seed »ç¿ë.... random_numbers # ... ¿ÏÀüÈ÷ ¶È°°Àº ¼ö¿ÀÌ ¹ß»ý. echo; echo RANDOM=2 # ´Ù¸¥ seed ·Î Àç½Ãµµ... random_numbers # ´Ù¸¥ ¼ö¿ ¹ß»ý. echo; echo # RANDOM=$$ ¶ó°í ÇÏ´Â °ÍÀº RANDOM ¿¡ ½ºÅ©¸³Æ®ÀÇ ÇÁ·Î¼¼½º ID·Î seed¸¦ ¼¼ÆÃÇÏ´Â °ÍÀÔ´Ï´Ù. # 'time' À̳ª 'date'·Î ÇÒ ¼öµµ Àְڳ׿ä. # ´õ ¸ÚÁö°Ô ÇØ º¸ÁÒ. SEED=$(head -1 /dev/urandom | od -N 1 | awk '{ print $2 }') # /dev/urandom(½Ã½ºÅÛ¿¡¼ Á¦°øÇÏ´Â Àǻ糼ö "µð¹ÙÀ̽º")¿¡¼ ¾òÀº Àǻ糼ö # ±× ´ÙÀ½ "od"¸¦ ÀÌ¿ëÇؼ Ãâ·Â °¡´ÉÇÑ(8Áø¼ö) ¼ýÀÚ·Î ÀÌ·ç¾îÁø ÁÙ·Î º¯È¯. # ¸¶Áö¸·À¸·Î "awk"¸¦ ½á¼ SEED ¿¡¼ ¾µ ÇÑ °³ÀÇ ¼ýÀÚ¸¦ »Ì¾Æ³¿. RANDOM=$SEED random_numbers echo; echo exit 0