怎样打印出grep后的部分内容? - 未名空间MITBBS历史存档

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怎样打印出grep后的部分内容?

怎样打印出grep后的部分内容?# Unix - 噫吁兮，危乎高哉

t*l2002-08-30 07:08

1 楼

for example,
1.grep "User Name:" user.txt
User Name: John
User Name: Mary
User Name: Michael
现在我想只打印出冒号后面的名字,并使之间隔显示在同一行里.怎么实现?
thanks.

D*e2002-08-30 07:08

2 楼

grep "User Name:" user.txt | awk -F "\:" '{print $2}' | tr '\n' ' '

【在 t*******l 的大作中提到】

: for example,
: 1.grep "User Name:" user.txt
: User Name: John
: User Name: Mary
: User Name: Michael
: 现在我想只打印出冒号后面的名字,并使之间隔显示在同一行里.怎么实现?
: thanks.

t*l2002-08-30 07:08

3 楼

doesn't work :))

【在 D**e 的大作中提到】

: grep "User Name:" user.txt | awk -F "\:" '{print $2}' | tr '\n' ' '

s*s2002-08-30 07:08

4 楼

no space after -F, and no need to use tr

【在 t*******l 的大作中提到】

: doesn't work :))

t*l2002-08-30 07:08

5 楼

this time it works, but nothing came out....

【在 s**s 的大作中提到】

: no space after -F, and no need to use tr

D*e2002-08-30 07:08

6 楼

what's the matter?

【在 t*******l 的大作中提到】

: doesn't work :))

t*l2002-08-30 07:08

7 楼

awk: syntax error near line 1
awk: bailing out near line 1

【在 D**e 的大作中提到】

: what's the matter?

D*e2002-08-30 07:08

8 楼

how do you chop off the newline without tr?

【在 s**s 的大作中提到】

: no space after -F, and no need to use tr

D*e2002-08-30 07:08

9 楼

leave spaces where appropriate.

【在 t*******l 的大作中提到】

: awk: syntax error near line 1
: awk: bailing out near line 1

c*z2002-08-30 07:08

10 楼

grep xxx |awk -F":" '{printf("%s ",$2);}'
the ' is the one next to L, the same key of "

【在 t*******l 的大作中提到】

: awk: syntax error near line 1
: awk: bailing out near line 1

c*t2002-08-30 07:08

11 楼

so many awk fans. Sigh, I don't know awk, but other common commands
work well too.
echo `grep xxx | cut -d: -f2`
Of course, it runs two instead of one, but I would assume that the
bottleneck was the grep part...

c*z2002-08-30 07:08

12 楼

cut is ok here, but awk is more powerful and can handle more complicated cas
es.
as to master a unix cmd tools is really not easy, to know how to use awk is
a better idea for me :)
anyway, gawk is available on almost all unix platform ( and i'm using gawk )

【在 c*****t 的大作中提到】

: so many awk fans. Sigh, I don't know awk, but other common commands
: work well too.
: echo `grep xxx | cut -d: -f2`
: Of course, it runs two instead of one, but I would assume that the
: bottleneck was the grep part...

t*l2002-08-30 07:08

13 楼

how to use it?:)

【在 c*****z 的大作中提到】

: cut is ok here, but awk is more powerful and can handle more complicated cas
: es.
: as to master a unix cmd tools is really not easy, to know how to use awk is
: a better idea for me :)
: anyway, gawk is available on almost all unix platform ( and i'm using gawk )