Hi,
Iam calling a C program from a Unix shell script. The (C) program reads encrypted username/password from a text file , decrypts and returns the decrypted string.
Is there any way i can return the decrypted string to Unix shell program.
My shell script uses the output of the program to... (11 Replies)
What I'm trying to do is to search through a list of files, and output the filename, followed by the lines that matched the pattern.
I'm matching the string "letters.moreletters" in any one of searched files, and the output I'm trying to get is:
program_1.txt
10 dsdsd sdsd dsd... (2 Replies)
Hi,
I'm having a requirement where I need to call a C program from a shell script and return the value from the C program to shell script.
I refered a thread in this forum. But using that command in the code, it is throwing an error
clear_text_password=$(get_password)
Error: bash:... (24 Replies)
Hey I am relatively new to Linux and shell scripting, looking for a spot of help with a script I am working on.
I am writing a script that counts the number of lines in all the files in a directory, sorts them by line number and then returns ONLY the file with the most lines.
Right now I can... (11 Replies)
Hi,
I have two files. 1st file has 1 column (huge file containing ~19200000 lines) and 2nd file has 2 columns (small file containing ~6000 lines).
#################################
huge_file.txt
a
a
ab
b
##################################
small_file.txt
a 1.5
b 2.5
ab ... (4 Replies)
The question is not as simple as the title... I have a file, it looks like this
<string name="string1">RZ-LED</string>
<string name="string2">2.0</string>
<string name="string2">Version 2.0</string>
<string name="string3">BP</string>
I would like to check for duplicate entries of... (11 Replies)
Hello, can someone help me how to find a word and 2 lines after it and then send the output to another file.
For example, here is myfile1.txt. I want to search for "Error" and 2 lines below it and send it to myfile2.txt
I tried with grep -A but it's not supported on my system.
I tried with awk,... (4 Replies)
Hello everyone,
Maybe somebody could help me with an awk script.
I have this input (field separator is comma ","):
547894982,M|N|J,U|Q|P,98,101,0,1,1
234900027,M|N|J,U|Q|P,98,101,0,1,1
234900023,M|N|J,U|Q|P,98,54,3,1,1
234900028,M|H|J,S|Q|P,98,101,0,1,1
234900030,M|N|J,U|F|P,98,101,0,1,1... (2 Replies)
I cannot seem to get what should be a simple awk one-liner to work correctly and cannot figure out why. I would like to use patterns from a specific field in one file as regex to search for matching strings in the entire line ($0) of another file.
I would like to output the lines of File2 which... (1 Reply)
Discussion started by: jvoot
1 Replies
LEARN ABOUT V7
grep
GREP(1) General Commands Manual GREP(1)NAME
grep, egrep, fgrep - search a file for a pattern
SYNOPSIS
grep [ option ] ... expression [ file ] ...
egrep [ option ] ... [ expression ] [ file ] ...
fgrep [ option ] ... [ strings ] [ file ]
DESCRIPTION
Commands of the grep family search the input files (standard input default) for lines matching a pattern. Normally, each line found is
copied to the standard output; unless the -h flag is used, the file name is shown if there is more than one input file.
Grep patterns are limited regular expressions in the style of ed(1); it uses a compact nondeterministic algorithm. Egrep patterns are full
regular expressions; it uses a fast deterministic algorithm that sometimes needs exponential space. Fgrep patterns are fixed strings; it
is fast and compact.
The following options are recognized.
-v All lines but those matching are printed.
-c Only a count of matching lines is printed.
-l The names of files with matching lines are listed (once) separated by newlines.
-n Each line is preceded by its line number in the file.
-b Each line is preceded by the block number on which it was found. This is sometimes useful in locating disk block numbers by con-
text.
-s No output is produced, only status.
-h Do not print filename headers with output lines.
-y Lower case letters in the pattern will also match upper case letters in the input (grep only).
-e expression
Same as a simple expression argument, but useful when the expression begins with a -.
-f file
The regular expression (egrep) or string list (fgrep) is taken from the file.
-x (Exact) only lines matched in their entirety are printed (fgrep only).
Care should be taken when using the characters $ * [ ^ | ? ' " ( ) and in the expression as they are also meaningful to the Shell. It is
safest to enclose the entire expression argument in single quotes ' '.
Fgrep searches for lines that contain one of the (newline-separated) strings.
Egrep accepts extended regular expressions. In the following description `character' excludes newline:
A followed by a single character matches that character.
The character ^ ($) matches the beginning (end) of a line.
A . matches any character.
A single character not otherwise endowed with special meaning matches that character.
A string enclosed in brackets [] matches any single character from the string. Ranges of ASCII character codes may be abbreviated
as in `a-z0-9'. A ] may occur only as the first character of the string. A literal - must be placed where it can't be mistaken as
a range indicator.
A regular expression followed by * (+, ?) matches a sequence of 0 or more (1 or more, 0 or 1) matches of the regular expression.
Two regular expressions concatenated match a match of the first followed by a match of the second.
Two regular expressions separated by | or newline match either a match for the first or a match for the second.
A regular expression enclosed in parentheses matches a match for the regular expression.
The order of precedence of operators at the same parenthesis level is [] then *+? then concatenation then | and newline.
SEE ALSO ed(1), sed(1), sh(1)DIAGNOSTICS
Exit status is 0 if any matches are found, 1 if none, 2 for syntax errors or inaccessible files.
BUGS
Ideally there should be only one grep, but we don't know a single algorithm that spans a wide enough range of space-time tradeoffs.
Lines are limited to 256 characters; longer lines are truncated.
GREP(1)