hey guys, how do i replace only a line within a file without messing up the rest of the contents of the file?
see, if possible can you guys give me a straight forward way to do this. i dont want a complex command. what i mean is i know i can accomplish this by using sed, well, i think i can,... (3 Replies)
I have a problem in the following code ...
while read line
do
#Get Line Number
OLDLINE=`sed -n $Lineno $filename`
echo "Un Changed Line : "$OLDLINE
echo "Enter a New Pattern : "
read NewPattern <&1
echo "NewPattern :"$NewPattern
NEWLINE=`cat $filename | sed -n... (1 Reply)
STEP 1
# Set variable
FILE=/tmp/mainfile
SEARCHFILE =/tmp/searchfile
# THIS IS THE MAIN FILE.
cat /tmp/mainfile
Interface Ethernet0/0 "outside", is up, line protocol is up
Hardware is i82546GB rev03, BW 100 Mbps
Full-Duplex(Full-duplex), 100 Mbps(100 Mbps)
MAC address... (6 Replies)
Hello,
I have two files that I need to compare and print out the line from file2 that has the first 6 fields matching the first 6 fields in file1. Complicating this are the following restrictions
1. file1 is only a few thousand lines at most and file2 is greater than 2 million
2. I need to... (7 Replies)
File 1
<html>ta da....unique file name I want to give file=>343...</html>
<html>da ta 234 </html>
<html>pa da 542 </html>
and so on...
File 2
343
234
542
and so on, each line in File 1 one also corresponds with each line in File 2
I have tried several grep, sed, while .. read, do,... (4 Replies)
Hi All,
I have a set of files named S5_SK1.chr01 S5_SK1.chr02 S5_SK1.chr03 ..... and the first line of these files is >SK1.chr01 >SK1.chr02 >SK1.chr03 ..... Can anyone suggest how I can change the first line of all these files with the filename itself? So my expected output for the first lines of... (14 Replies)
I have a file which has a list in it
pop
triangle
people
slow
fast
What I want to do is search this list and replace people with humans do the list looks like this:
pop
triangle
human
slow
fast
I think i use something like this....
if cat /list.txt | grep -q 'people' ; then (9 Replies)
Hi all,
I need to replace a line
export TZ=xxxxxxxx
with the line
export TZ=$1
Now, "xxxxxxxx" in the above line is some unknown string and $1 is a parameter. I want the content of $1 to be replaced with "xxxxxxxx".
Kindly help me how to do this in the shell scripting. (5 Replies)
Good day,
I have a list of regular expressions in file1. For each match in file2, print the containing line and the line after.
file1:
file2:
Output:
I can match a regex and print the line and line after
awk '{lines = $0} /Macrosiphum_rosae/ {print lines ; print lines } '
... (1 Reply)
Dear friends,
I have two files. One with all IDs(in a single field) . And another with data(of which say field 5 is ID). I want to create an array of IDs using first file and
while reading second file if the ID appears in the array I need to print $0 else skip.
After a long gap I am... (6 Replies)
Discussion started by: paresh n doshi
6 Replies
LEARN ABOUT OPENDARWIN
cat
CAT(1) BSD General Commands Manual CAT(1)NAME
cat -- concatenate and print files
SYNOPSIS
cat [-benstuv] [file ...]
DESCRIPTION
The cat utility reads files sequentially, writing them to the standard output. The file operands are processed in command-line order. If
file is a single dash ('-') or absent, cat reads from the standard input. If file is a UNIX domain socket, cat connects to it and then reads
it until EOF. This complements the UNIX domain binding capability available in inetd(8).
The options are as follows:
-b Number the non-blank output lines, starting at 1.
-e Display non-printing characters (see the -v option), and display a dollar sign ('$') at the end of each line.
-n Number the output lines, starting at 1.
-s Squeeze multiple adjacent empty lines, causing the output to be single spaced.
-t Display non-printing characters (see the -v option), and display tab characters as '^I'.
-u The -u option guarantees that the output is unbuffered.
-v Display non-printing characters so they are visible. Control characters print as '^X' for control-X; the delete character (octal
0177) prints as '^?'. Non-ASCII characters (with the high bit set) are printed as 'M-' (for meta) followed by the character for the
low 7 bits.
DIAGNOSTICS
The cat utility exits 0 on success, and >0 if an error occurs.
EXAMPLES
The command:
cat file1
will print the contents of file1 to the standard output.
The command:
cat file1 file2 > file3
will sequentially print the contents of file1 and file2 to the file file3, truncating file3 if it already exists. See the manual page for
your shell (i.e., sh(1)) for more information on redirection.
The command:
cat file1 - file2 - file3
will print the contents of file1, print data it receives from the standard input until it receives an EOF ('^D') character, print the con-
tents of file2, read and output contents of the standard input again, then finally output the contents of file3. Note that if the standard
input referred to a file, the second dash on the command-line would have no effect, since the entire contents of the file would have already
been read and printed by cat when it encountered the first '-' operand.
SEE ALSO head(1), more(1), pr(1), sh(1), tail(1), vis(1), zcat(1), setbuf(3)
Rob Pike, "UNIX Style, or cat -v Considered Harmful", USENIX Summer Conference Proceedings, 1983.
STANDARDS
The cat utility is compliant with the IEEE Std 1003.2-1992 (``POSIX.2'') specification.
The flags [-benstv] are extensions to the specification.
HISTORY
A cat utility appeared in Version 1 AT&T UNIX. Dennis Ritchie designed and wrote the first man page. It appears to have been cat(1).
BUGS
Because of the shell language mechanism used to perform output redirection, the command ``cat file1 file2 > file1'' will cause the original
data in file1 to be destroyed!
BSD September 15, 2001 BSD