tit:replace
type:$type_both
syntax:!replace [internal] `s1' by `s2' in `string'\
!replace `obj' `ident' by `s' in `string'
mean:´®²Ù×÷. <p>\
ÔÚµÚÒ»¾äµÄÐÎʽÏÂ, ÏȶÔ.\
È»ºóËùÓгöÏÖ×Ó´® `s1' µÄµØ·½¶¼Ìæ»»³É `s2'. <br>\
Èç¹ûûÓйؼü´Ê `internal',\
Ôòµ÷Óà Linux ÃüÁî `sed' Íê³ÉÌæ»»,\
ËùÒÔÔÚ `s1' ºÍ `s2' Àï¿É½ÓÊÜÕýÔò±í´ïʽ.\
ÏêÇéÇë²Î¿´ `sed' µÄ˵Ã÷. <p>\
ÔÚµÚ¶þ¾äµÄÐÎʽÏÂ, `obj' ¿ÉÒÔÊÇ `char',\
`word', `item' »ò `line'.\
¾¹ý¶Ô `string' ×÷±äÁ¿Ìæ»»ºó,\
`string' ÄÚÓë `ident' ÏàͬµÄ´Ê¡¢Ïî»òÐб»Ìæ´úΪ\
`s'. <br>\
`ident' ¿ÉÒÔÊÇÒ»¸ö´®, ´ËʱËùÓÐÓë `ident' Æ¥ÅäµÄ¶ÔÏó\
(´Ê¡¢Ïî»òÐÐ)½«±»Ìæ»». `ident' Ò²¿ÉÒÔÊÇÒ»¸öÊý(Õý»ò¸ºÕûÊý `n'),\
Ç°Ãæ¹ÚÒÔ´Ê `number'. Õâʱ±»Ìæ»»µÄÊÇµÚ `n' ¸ö¶ÔÏó\
(µ± n<0 ʱ, ±»Ìæ»»µÄÊǵ¹ÊýµÚ `n' ¸ö¶ÔÏó.)