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请教:Variable in sed command

请教:Variable in sed command# Unix - 噫吁兮，危乎高哉

r*s2002-03-19 08:03

1 楼

Hi, everybody,
I tried to use a shell script to do a for loop:
#!...bash
for i in (5, 10, 15, 20) do;
sed 's/bpp=64/bpp=$i/g' myfile.c > myfile2.c
~~
done
However, each time it executes, "bpp=64" becomes "bpp=$i" instead of
"bpp=5" ......
I have no idea how to make the $i inside sed command to be a real variable.
Anybody has a suggestion for it?
Thanks a lot!

m*t2002-03-19 08:03

2 楼

try sed 's/bpp=64/bpp=\$\{i\}/g' myfile.c > myfile2.c

【在 r*****s 的大作中提到】

: Hi, everybody,
: I tried to use a shell script to do a for loop:
: #!...bash
: for i in (5, 10, 15, 20) do;
: sed 's/bpp=64/bpp=$i/g' myfile.c > myfile2.c
: ~~
: done
: However, each time it executes, "bpp=64" becomes "bpp=$i" instead of
: "bpp=5" ......
: I have no idea how to make the $i inside sed command to be a real variable.

r*o2002-03-19 08:03

3 楼

What if I want to use the matching variable as an index of an array?
What I wanted to do is:
infile:
SRC_1
SRC_2
SRC_3
SRC_4
SRC_5
change it to outfile:
SRC_2
SRC_3
SRC_4
SRC_1
SRC_5
(Ultimately, I will want to try all the possible sequences of
SRC_1 to SRC_5
So what I did:
set array = (2 3 4 1 5) #this array can be changed by script automatically
sed "/SRC_[1-5]/s/$[1-5]$/$array[\1]/" infile > outfile
But it doesn't recognize \1 as the index of the array,
anyway to solve it? Thanks.

variab

【在 m*******t 的大作中提到】

: try sed 's/bpp=64/bpp=\$\{i\}/g' myfile.c > myfile2.c