[Shell Practice]--awk Exercises

1. What is the difference between sed and awk?

(1) Awk: Operations by column (domain); sed: line by row
(2) awk: Text processing language, suitable for extracting text; SED: non-interactive editor for editing text

2. Which parameter does awk use as a split parameter when it is working on a domain?

-F

3. Please print out the first domain of/etc/passwd and add "user account:" Before the contents of the first domain.
# cat/etc/passwd |awk-f: ' {print ' User account: ' $ '

4. Print out the third and fourth domains of/etc/passwd
# awk-f: ' {print $ ' \ t ' $4} '/etc/passwd

5. Match/etc/passwd third field greater than 100 shows full information
# CAT/ETC/PASSWD |awk-f: ' {if ($3>100) print$0} '

6. Please print the first domain, and the print header information is: This is the system user, the print tail information is: "================"
# cat/etc/passwd |awk-f: ' Begin{print "This is the system user"} {print $} end{print "================"} '

7. Print line numbers less than 15, and the last field matches bash information.
# cat/etc/passwd |awk-f: ' {if ($NR <15 && $NF ~/bash/) print$0} '

8. Please print out the first field matching daemon information.
# cat/etc/passwd |awk-f: ' $1== ' daemon '

10. Please print out the sum of the third field numbers
# cat/etc/passwd |awk-f: ' {sum=sum+$3}end{print sum} '
# cat/etc/passwd |awk-f: ' {sum=sum+$3}; End{print sum} '

11. Replace root in/etc/passwd with Gongda, and remember to temporarily replace the output screen to see the effect.
# cat/etc/passwd |awk-f: ' Gsub (/root/, "Gongda") {print $} '

12. Please match the information in the end of the last field bash of passwd, how many
# awk-f: ' ($NF ~ /bash/) {print NR} '/etc/passwd |wc-l
# cat/etc/passwd |awk-f: ' {if ($NF ~/bash/) print$0} ' |wc-l

13. Please also match the information in the passwd file, with mail and bash keywords
# cat/etc/passwd |awk-f: ' $0~/root|mail/'
# awk-f: ' {if ($0~/mail/| | $0~/bash/) print $} '/etc/passwd

14. Please match the information about the passwd third domain total greater than 500.
# cat/etc/passwd |awk-f: ' {if ($3>500) print $} '

15. The contents of the file are as follows:
Mike harrington:[510] 548-1278:250:100:175
Christian dobbins:[408] 538-2358:155:90:201
Susan dalsass:[206] 654-6279:250:60:50
Archie mcnichol:[206] 548-1348:250:100:175
Jody savage:[206] 548-1278:15:188:150
Guy quigley:[916] 343-6410:250:100:175
Dan savage:[406] 298-7744:450:300:275
Nancy mcneil:[206] 548-1278:250:80:75
John goldenrod:[916] 348-4278:250:100:175
Chet main:[510] 548-5258:50:95:135
Tom savage:[408] 926-3456:250:168:200
Elizabeth stachelin:[916] 440-1763:175:75:300
which
Mike Harrington Name
[510] 548-1278 Telephone
250:100:175 donations in the past three months

(1) Show all phone numbers
# awk-f: ' {print $} ' file

(2) Show Dan's phone number
# awk-f: ' {if ($1~/dan/) print$2} ' file

(3) Show Susan's name and phone number
# awk-f: ' {if ($1~/susan/) print$1,$2} ' file

(4) Show all surnames starting with D
# awk-f: ' {if ($1~/^d/) print$1} ' file

(5) Show all names beginning with a C or E
# awk-f: ' {if ($1~/^[c| e]/) print$1} ' file

(6) Displays all names with only four characters, where you can use the length function, for example: Length ($) ==10 the character 10
# cat file |awk-f: ' {print$1} ' |awk ' {if (length ($) ==4) print '} '

(7) Show all names with area code 916
# cat file |awk ' {print$2} ' |awk-f: ' {if ($2~/916/) print$1} '

(8) Show Mike's donation. Each value is displayed with a $ start. such as $250$100$175
# cat file |awk-f: ' {if ($1~/mike/) print "$" $ "$" $ "$4" $ "$"

(9) display last name followed by a comma and a name
# cat file |awk-f: ' {print$1} ' |awk ' {print$2 ', ' $ '

[Shell Practice]--awk Exercises