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unix shell help?

unix shell help?# Unix - 噫吁兮，危乎高哉

j*y2003-09-25 07:09

1 楼

what's the meaning the following expression?
vi load_image.sh
pls be as detailed as possible, thanks,

T*r2003-09-25 07:09

2 楼

1,$: from the first line of the file to the last line
s: find some matching pattern, and replace with another pattern
/: begin the matching pattern
.: match any character
*: match any number of characters, i.e., 0 - any characters
/: end of the matching pattern, begin the replacing pattern
.\/load_image.pl Image\/: replacing pattern is ./load_image.pl Image/
note the difference between a single '/' and '\/'. for '/', it is
the delimit character between patterns. for '\/', it represents th

【在 j***y 的大作中提到】

: what's the meaning the following expression?
: vi load_image.sh
: pls be as detailed as possible, thanks,

j*y2003-09-25 07:09

3 楼

I find this is the most difficult part. All others I can understand.
So with "&" present, the effect is to insert the string "./load_image.pl
Image/" in the beginning of every line in the file, coz "&" tells it not to
match anything, right?

【在 T********r 的大作中提到】

:
: 1,$: from the first line of the file to the last line
: s: find some matching pattern, and replace with another pattern
: /: begin the matching pattern
: .: match any character
: *: match any number of characters, i.e., 0 - any characters
: /: end of the matching pattern, begin the replacing pattern
: .\/load_image.pl Image\/: replacing pattern is ./load_image.pl Image/
: note the difference between a single '/' and '\/'. for '/', it is
: the delimit character between patterns. for '\/', it represents th

T*r2003-09-25 07:09

4 楼

frankly speaking, I do not know the meaning of & either. just made a guess
here, hehe. ok, my guess might be wrong. & probably means the matched
pattern. check the following link:
http://www.unicode.org/reports/tr18/

【在 j***y 的大作中提到】

:
: I find this is the most difficult part. All others I can understand.
: So with "&" present, the effect is to insert the string "./load_image.pl
: Image/" in the beginning of every line in the file, coz "&" tells it not to
: match anything, right?

j*y2003-09-25 07:09

5 楼

Yes, you are right on this point.
http://www.cis.tugraz.at/zid/peter/unix/regular.html

【在 T********r 的大作中提到】

:
: frankly speaking, I do not know the meaning of & either. just made a guess
: here, hehe. ok, my guess might be wrong. & probably means the matched
: pattern. check the following link:
: http://www.unicode.org/reports/tr18/