I can think of two approaches:
Store the data to display in memory while you figure out what is 'in' and what's 'out'.
Run through the file a couple of times.
As I don't know how big the file is, we'll go with the multiple passes solution - it's ugly but it has a predictable memory footprint
Hi,
I was given a question like this:
Write a program which reads a set of arguments from the standard input. Note
that there is no limit for the number of arguments. The first argument is the file
name and the other arguments are searched in the given file. For each argument, it displays... (3 Replies)
Hi everybody
for file in *
#Bash performs filename expansion
#+ on expressions that globbing recognizes.
do
output="`grep -n "$1" "$file"`"
echo "$file: `expr "$output" : '\(^.*$\)'`"
done
In the above bash script segment, I try to print just the first line of string named... (3 Replies)
Hey guys, I have a file that I've slowly been awking, seding, and greping for data entry. I am down to pull the addresses out to insert them into an excel file. Each address is a few lines, but i want to put a semicolon delimiter in between each address so I can export the text file into excel and... (6 Replies)
Good Day,
Im new to scripting especially awk and sed. I just would like to ask help from you guys about a sed command that prints the line immediately after a regexp, but not the line containing the regexp.
sed -n '/regexp/{n;p;}' filename
What if my regexp is 3 word or a sentence. Im... (3 Replies)
I have successfully used regexp and sed to insert a newline before or after a line containing a matched pattern /WORD/. However, I want to insert a newline immediately following /WORD/ and not after the -line- containing the pattern matched. I can match a pattern, but it is matched via a wild card... (2 Replies)
Hi,
I have a file, say files_list, as below (o/p of ls -R cmd)
$ cat files_list
/remote/dir/path/to/file:
sub-dir1
sub-dir2
sub-dir3
...
/remote/dir/path/to/file/sub-dir1:
remote_file1.csv.tgz
<blank line 1>
/remote/dir/path/to/file/sub-dir2:
remote_file2.csv.tgz
<blank... (3 Replies)
Hi All
I'm trying to extract the line just above a regexp and all lines after this.
I'm currently doing this in two steps
sed -n -e "/^+---/{g;p;}" -e h oldfile.txt > modified.txt
sed -e "1,/^+---/d" -e "/^$/d" oldfile.txt >>modified.txt
Sample
sometext will be here
sometext will be... (3 Replies)
Hi,
I want to read a live log file line by line and considering those line which start from time stamp;
Below code I am using, which read line but throws an exception when comparing line that does not contain error code
tail -F /logs/COMMON-ERROR.log | while read myline; do... (2 Replies)
I'm looking for a way to print the 4th line back from a regular expression. Kind of like the below but it has to be the 4th line before the regexp.
Print the line immediately before regexp, but not the line containing the regexp.
sed -n '/regexp/{g;1!p;};h'
here is an example of logs(i... (11 Replies)
Hi All,
I need to print the characters in the previous line just before the regular expression match
Please have a look at the input file as attached
I need to match the regular expression ^ with the character of the previous like and also the pin numbers
and the output file should be like... (6 Replies)
Discussion started by: kshitij
6 Replies
LEARN ABOUT SUNOS
egrep
egrep(1)egrep(1)NAME
egrep - search a file for a pattern using full regular expressions
SYNOPSIS
/usr/bin/egrep [-bchilnsv] [-e pattern_list] [-f file] [strings] [file...]
/usr/xpg4/bin/egrep [-bchilnsvx] [-e pattern_list] [-f file] [strings] [file...]
The egrep (expression grep) utility searches files for a pattern of characters and prints all lines that contain that pattern. egrep uses
full regular expressions (expressions that have string values that use the full set of alphanumeric and special characters) to match the
patterns. It uses a fast deterministic algorithm that sometimes needs exponential space.
If no files are specified, egrep assumes standard input. Normally, each line found is copied to the standard output. The file name is
printed before each line found if there is more than one input file.
/usr/bin/egrep
The /usr/bin/egrep utility accepts full regular expressions as described on the regexp(5) manual page, except for ( and ), ( and ), {
and }, < and >, and
, and with the addition of:
1. A full regular expression followed by + that matches one or more occurrences of the full regular expression.
2. A full regular expression followed by ? that matches 0 or 1 occurrences of the full regular expression.
3. Full regular expressions separated by | or by a NEWLINE that match strings that are matched by any of the expressions.
4. A full regular expression that can be enclosed in parentheses ()for grouping.
Be careful using the characters $, *, [, ^, |, (, ), and in full regular expression, because they are also meaningful to the shell. It is
safest to enclose the entire full regular expression in single quotes '... '.
The order of precedence of operators is [], then *?+, then concatenation, then | and NEWLINE.
/usr/xpg4/bin/egrep
The /usr/xpg4/bin/egrep utility uses the regular expressions described in the EXTENDED REGULAR EXPRESSIONS section of the regex(5) manual
page.
The following options are supported for both /usr/bin/egrep and /usr/xpg4/bin/egrep:
-b Precede each line by the block number on which it was found. This can be useful in locating block numbers by context (first
block is 0).
-c Print only a count of the lines that contain the pattern.
-e pattern_list Search for a pattern_list (full regular expression that begins with a -).
-f file Take the list of full regular expressions from file.
-h Suppress printing of filenames when searching multiple files.
-i Ignore upper/lower case distinction during comparisons.
-l Print the names of files with matching lines once, separated by NEWLINEs. Does not repeat the names of files when the pat-
tern is found more than once.
-n Precede each line by its line number in the file (first line is 1).
-s Work silently, that is, display nothing except error messages. This is useful for checking the error status.
-v Print all lines except those that contain the pattern.
/usr/xpg4/bin/egrep
The following option is supported for /usr/xpg4/bin/egrep only:
-x Consider only input lines that use all characters in the line to match an entire fixed string or regular expression to be matching
lines.
The following operands are supported:
file A path name of a file to be searched for the patterns. If no file operands are specified, the standard input is used.
/usr/bin/egrep
pattern Specify a pattern to be used during the search for input.
/usr/xpg4/bin/egrep
pattern Specify one or more patterns to be used during the search for input. This operand is treated as if it were specified as
-epattern_list.
USAGE
See largefile(5) for the description of the behavior of egrep when encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).
See environ(5) for descriptions of the following environment variables that affect the execution of egrep: LC_COLLATE, LC_CTYPE, LC_MES-
SAGES, and NLSPATH.
The following exit values are returned:
0 If any matches are found.
1 If no matches are found.
2 For syntax errors or inaccessible files (even if matches were found).
See attributes(5) for descriptions of the following attributes:
/usr/bin/egrep
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
|CSI |Not Enabled |
+-----------------------------+-----------------------------+
/usr/xpg4/bin/egrep
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWxcu4 |
+-----------------------------+-----------------------------+
|CSI |Enabled |
+-----------------------------+-----------------------------+
fgrep(1), grep(1), sed(1), sh(1), attributes(5), environ(5), largefile(5), regex(5), regexp(5), XPG4(5)
Ideally there should be only one grep command, but there is not a single algorithm that spans a wide enough range of space-time tradeoffs.
Lines are limited only by the size of the available virtual memory.
/usr/xpg4/bin/egrep
The /usr/xpg4/bin/egrep utility is identical to /usr/xpg4/bin/grep -E (see grep(1)). Portable applications should use /usr/xpg4/bin/grep
-E.
23 May 2005 egrep(1)
01-07-2008
