Frequently Used Unix Commands

Useful Unix Commands with Example

1. Check 6th Columns without Null value from any file

            nawk -F"|" '($6!="")' FileName > test_24_ok

2. Check 6th Columns with Null value from any file

 nawk -F"|" '($6=="")' FileName > test_24

3. Finding distinct row's from any file

awk -F"|" '{print $32 }' File_Name.txt | sort -u

4. For creating direcory from another location

mkdir -p /u05/PRODDSS/data3/srcfiles/mcd

# Send mail through Unix

/usr/bin/mailx -s "Mount Point status" -r EmergencyMail 

 devendrakumar.yadav@relianceada.com  /Path/diskutilization.txt

/usr/bin/mailx –s “Subject Line” –r “Sender Mail ID/XYZ” Receipient Mail Id  Attachment

5. For going 37072948 no’s rows in a file then
     awk NR==37072948 S_VLD_COMPLETE_DATA_2008-10-23.dat

6. For File spliting in Unix 
     split -37072945 S_VLD_COMPLETE_DATA_2008-10-23.dat

      (automatically file splitted into total rows/given row no)

7. For deleting Particular record from a large file

    where first column No's is '9999705895' 
    cat  merge_R_VOI_27_2008-10-27.dat|grep -v 9999705895 > test.txt

8. Sagrigate Substrings 

     awk -f"|" '{print substr($1,1,4)"-"substr($1,5,2)}' test.txt |more

9. Display 1,2,3,18,19 columns from that file 
     awk -F"," '{print $1,$2,$3,$18,$19 }' File_name | head -20

10. Cut a string from a file and display without spacing  
     awk 'BEGIN {OFS="|"}{print $1,$2,$3,substr($12,1,4)"-"substr($12,5,2)}' file_name 
     awk -F"n" '{ print substr($1,1,4) }' file_name

11. Display particular column($1 for 1st column) from given file 
      awk -F"," '{print $1}' FileName

12. Command For search a file in unix  
      find /u04/ -name File_name -print

13. To print Number of Columns  
      awk 'BEGIN{FS="|"}{print NF}' File_Name | head -3

14. Print columns which is less or greater than 500 
      nawk 'BEGIN{FS=OFS="|"}{if(NF > 500 || NF < 500){print $0}}' File_Name 

Devendra1.dat File is having onlyNF=7 Record's

           ð nawk 'BEGIN{FS=OFS="|"}{if(NF==7){print $0}}' Devendra.dat 

Testing a file with first colum having "200903"

            ðawk -F"|" '{if($1=="200903")}{print $0}' S_04-01.dat 

15.For serch and replace in VI Editor

%s/old/new/g  
%s/20081215/20081115/g

16.In Fix Width File Search or cut

awk -F"n" '{ print substr($1,124,8)}' File name  

( $1 means whole string, 124th position upto + 8th position display)

17.For Updating Crontab using VI Editor

in Command line type

EDITOR=vi then Enter  then 

export EDITOR Then Type

Crontab –e

18.For concatinate two files same columns in another file

           paste file1 file2 > file3

19.For changing all albhabets in Capital letter from any file

            tr -s '[a-z]' '[A-Z]' < File_Name

20. ping to server in unix

/usr/sbin/ping 97.253.32.155

21.Take count from any file having '2009-02' records

awk -F"," '{print $5}' R_SMS_CDR_2009-04-02.dat| grep '2009-02' | wc -l

22.compare any substring from a file

nawk 'BEGIN{FS=","}{if(substr($3,1,7)=="2009-03"){print $0}}' test.txt

23.for copying whole directories

 tar -cvf ScriptBKP.tar /u06/srcfiles/scriptbackup/*

             tar -xvf ScriptBKP.tar

24.Insert '2' in all record's of end of every row in file DEV_TEST.TXT 

sed 's/$/|2/' DEV_TEST.TXT

25. For Executing Command Continuosly or looping

while true ; do smat -d | wc -l ; sleep 2 ; echo "==================="; done ;

while true ; do ls -lrt | wc -l ; sleep 2 ; echo "====================="; done ;

26. Display time also in unix prompt

PS1="\u-\t$"

27.Print Particular (2nd) line from any file

sed -n '2,2p;2q' R_2009-07-17_03_03.dat

            sed -n '5,5p;5q' R_2009-08-28_00_00.dat | awk -F"," '{print $51}'

28.Convert '2009-03-31' in 20090331

MDT=`echo $RDT|cut -c1-4,6-7,9-10` ; export MDT

29. Current Month Calculation ==>

MON1=`echo $RecordDate|cut -c6-7`

Year=`echo $RecordDate|cut -c1-4`

cal $MON1 $Year|awk NR==1|cut -c4-6 > CurrMonth

MON=`tr '[a-z]' '[A-Z]' < CurrMonth`

30. Connect any server through script and ftp the files 

     echo "Connecting 97.253.48.8"

     ftp -n 97.253.48.8 <<!

     quote user devendra1

     quote pass devendraPwd

     binary

     cd /app_inrich/OUTPUT_INTERFACE/call_hist/dump/

     lcd /u04/PisPath/pisfiles

     prompt

     mget DSS_INRich_subscriber_info$RD.txt

     quit

31. Output Of Date Command in unix

operator-17:28:11$ date

             Thu Nov 19 17:35:46 IST 2009

32. Output Of Cal Command in unix

operator-17:35:47$ cal

              November 2009

 S  M Tu  W Th  F  S

 1  2  3  4  5  6  7

 8  9 10 11 12 13 14

15 16 17 18 19 20 21

22 23 24 25 26 27 28

29 30

33. Print some particular columns from any file

operator-17:42:12$ls -ltr *NOV*2009-11-17*dat

-rw-rw-r--   1 operator adhoc    554 Nov 17 18:00 R_VOI_2009-11-17_14_14.dat

operator-17:42:19$ls -ltr *NOV*2009-11-17*dat |awk '{print $1,"|",$2,"|",$3,"VMA"}'

-rw-rw-r-- | 1 | operator VMA

            ls -ltr *JAN*2009-02-27*dat|awk '{print $1,"|",$2,"|",$3,"VMA"}'

34. Remove Empty Lines from any Files.

       sed '/^$/d' /tmp/myFile.txt  > /tmp/Output.txt