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sed question??

sed question??# Unix - 噫吁兮，危乎高哉

d*y2002-09-05 07:09

1 楼

Hi ,
I want to use sed on Unix to do this:
1. I have a string called tmp="12 23 34"
2. I want to replace all the space in this string with a new line and
dump it to a file
3. finally this file looks like this: 12
23
34
I tried this: print $tmp | sed 's/ /\n/g' it didn't work, so somebody
help????
Thanks

r*s2002-09-05 07:09

2 楼

你没有认识到sed的机制，每次读一行，在行内进行一些替换删除操作，
再读入下一行。我先给个awk的范例吧。UNIX总是有多解的，大家来想啊~

【在 d*****y 的大作中提到】

: Hi ,
: I want to use sed on Unix to do this:
: 1. I have a string called tmp="12 23 34"
: 2. I want to replace all the space in this string with a new line and
: dump it to a file
: 3. finally this file looks like this: 12
: 23
: 34
: I tried this: print $tmp | sed 's/ /\n/g' it didn't work, so somebody
: help????

r*s2002-09-05 07:09

3 楼

[7:06pm] cat t
12 34 56
[7:06pm] cat xixi.awk
BEGIN {FS=" "}
{
x1=$1
x2=$2
x3=$3
printf("%s\n", x1)
printf("%s\n", x2)
printf("%s\n", x3)
}
[7:06pm] awk -f xixi.awk t
12
34
56
[7:06pm]

【在 r********s 的大作中提到】

: 你没有认识到sed的机制，每次读一行，在行内进行一些替换删除操作，
: 再读入下一行。我先给个awk的范例吧。UNIX总是有多解的，大家来想啊~

r*s2002-09-05 07:09

4 楼

下面这个用cut命令：
[8:35pm] cat t
12 34 56
[8:36pm] cut -d " " -f1 t ; cut -d " " -f2 t ; cut -d " " -f3 t
12
34
56
[8:36pm]
可以写一个script来偷懒：
# shell script to replace space with new line
#!/bin/sh
echo -n "Enter the input file name: "
read input
cut -d " " -f1 $input; cut -d " " -f2 $input; cut -d " " -f3 $input
以下为运行结果：
[8:44pm] sh xixi
Enter the input file name: t
12
34
56
[8:46pm]

r*s2002-09-05 07:09

5 楼

cool. by 'man tr', I learn sth about translate lowercase to uppercase.
[11:52pm] cat t
abcd
[11:52pm] cat t | tr -s '[:lower:]' '[:upper:]'
ABCD

d*y2002-09-05 07:09

6 楼

Thanks to rhinoceros and killme, your comments are very helpful.
Actually I also tried this and it works well:
print $tmp | tr -s ' ' '[\012*]'
have a nice day
- danny

【在 r********s 的大作中提到】

: cool. by 'man tr', I learn sth about translate lowercase to uppercase.
: [11:52pm] cat t
: abcd
: [11:52pm] cat t | tr -s '[:lower:]' '[:upper:]'
: ABCD