Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

search for string and replace backwards

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting search for string and replace backwards
# 1  
Old 10-10-2009
search for string and replace backwards
I'm new to Unix scripting and I'm not sure if this can be done. Example:

search (grep) in a file for 'Control ID' and then replace with 4 blanks 7 bytes before 'Control ID.

input
"xxxxxx1234xxxxxxxControl IDxxxxxx"

output:
"xxxxxx xxxxxxxControl IDxxxxxx"

thanks!
# 2  
Old 10-10-2009
Hi.

Using sed:

Code:
sed "s/\(.*\)....\(.\{7\}Control ID.*\)/\1 \2/" input_file
 
xxxxxx xxxxxxxControl IDxxxxxx

# 3  
Old 10-10-2009
thanks a lot..
# 4  
Old 10-12-2009
This works, but replaces with 1 space not 4 spaces
Scott,

the command works ok, but 1 space replaces 4 bytes which compresses the file:

sed "s/\(.*\)....\(.\{7\}Control ID.*\)/\1 \2/"

In:
abcde****1234567Control ID890

to:
abcde 1234567Control ID890

need:
abcdebbbb1234567Control ID890

with b= space

Thanks!
# 5  
Old 10-12-2009
Hi.

Add some spaces between \1 and \2

Code:
sed "s/\(.*\)....\(.\{7\}Control ID.*\)/\1    \2/" file2
xxxxxx    xxxxxxxControl IDxxxxxx

# 6  
Old 10-12-2009
Thanks Scott! that worked..

---------- Post updated at 11:12 AM ---------- Previous update was at 09:26 AM ----------

when I try to run this on my production file it does not work. I think it's the file size or record length issue. Does sed have a limit for record lenght? should I try awk instead?
# 7  
Old 10-12-2009
Hi.

No, it doesn't.

I just ran it on a file with a record (line) length of 750,000, and it worked fine.

Please state what the problem is (error message, etc.), and show what you did.

Thanks.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Search partial string in a file and replace the string - UNIX

I have the below string which i need to compare with a file and replace this string in the file which matches closely. Can anyone help me on this. string(Scenario 1)- user::r--,user::ourfrd:r-- String(Scenario 2)- user::r-- File **** # file: /local/Desktop/myfile # owner: me # group:... (6 Replies)
Discussion started by: sarathy_a35
6 Replies

2. UNIX for Dummies Questions & Answers

Search for a string,delete the line and replace with new string in a file

Hi Everyone, I have a requirement in ksh where i have a set of files in a directory. I need to search each and every file if a particular string is present in the file, delete that line and replace that line with another string expression in the same file. I am very new to unix. Kindly help... (10 Replies)
Discussion started by: Pradhikshan
10 Replies

3. Shell Programming and Scripting

Sed: find and replace backwards, until string

Some help please: Need to find string ||(everything in front of it)B0300|| and replace it with ||0|| globally In: 16112121||||0||0||0||0||0||52||52||0||0||0||0||1507200053342B0300||1507200053342B0300||0||0||0||0700 Out: 16112121||||0||0||0||0||0||52||52||0||0||0||0||0||0||0||0||0||0700 ... (4 Replies)
Discussion started by: drbiloukos
4 Replies

4. Shell Programming and Scripting

Search backwards to certain string

Hi, I'm using the following to do a backwards search of a file for a string sed s/^M//g FILE | nawk 'c-->0;$0~s{if(b)for(c=b+1;c>1;c--)print r;print;c=a}b{r=$0}' b=10 a=0 s="9005"|grep "policy "|sort -u |awk '{print $4}'|cut -c2-10 My issue is that because I'm looking back 10 lines it's... (11 Replies)
Discussion started by: SaltyDog
11 Replies

5. Shell Programming and Scripting

awk - replace number of string length from search and replace for a serialized array

Hello, I really would appreciate some help with a bash script for some string manipulation on an SQL dump: I'd like to be able to rename "sites/WHATEVER/files" to "sites/SOMETHINGELSE/files" within the sql dump. This is quite easy with sed: sed -e... (1 Reply)
Discussion started by: otrotipo
1 Replies

6. Shell Programming and Scripting

Search, replace string in file1 with string from (lookup table) file2?

Hello: I have another question. Please consider the following two sample, tab-delimited files: File_1: Abf1 YKL112w Abf1 YAL054c Abf1 YGL234w Ace2 YKL150w Ace2 YNL328c Cup9 YDR441c Cup9 YDR442w Cup9 YEL040w ... File 2: ... ABF1 YKL112W ACE2 YLR131C (9 Replies)
Discussion started by: gstuart
9 Replies

7. UNIX for Dummies Questions & Answers

Search for a string and replace the searched string in the same position in samefile

Hi All, My requisite is to search for the string "0108"(which is the year and has come in the wrong year format) in a particular column say 4th column in a tab delimited file and then replace it with 2008(the correct year format) in the same position where 0108 was found in the same file..The... (27 Replies)
Discussion started by: ganesh_248
27 Replies

8. Shell Programming and Scripting

search backwards relative to a string

Hi, I have to search for first occurenceof string str1 in a file(>5GB). Now, after I have that , I have to search backwards from that offset till I get another string str2. I should also be able to get the new string str2's offset. Similarly, I look for last occurence of str1 and then... (1 Reply)
Discussion started by: finder255
1 Replies

9. Shell Programming and Scripting

Search backwards

Hi, I have a variable , lets say a=/disk1/net/first.ksh i need to grep "first.ksh" everytime "a" gets changed dynamically and i do not know how many '"/" are there in my variable. Can somebody help me out. (9 Replies)
Discussion started by: giri_luck
9 Replies

10. Shell Programming and Scripting

Perl: Search for string on line then search and replace text

Hi All, I have a file that I need to be able to find a pattern match on a line, search that line for a text pattern, and replace that text. An example of 4 lines in my file is: 1. MatchText_randomNumberOfText moreData ReplaceMe moreData 2. MatchText_randomNumberOfText moreData moreData... (4 Replies)
Discussion started by: Crypto
4 Replies
Login or Register to Ask a Question