Hi...
I'm new here and i have a Q...
How do i get only the number from a string?
like from "rlvol11" i want to get 11
or from "lvol4" i want to get 4
what commands should i use at my script?
thanx 4 the help!
Eliraz. (13 Replies)
I writing my script and got stuck in this function. Can someone help me?
I need to extract out the numbers inside a string.
Ex:
INPUT -> OUTPUT
abcdef123 -> 123
abc123def -> 123
123abcdef -> 123
a123bc45d -> 123 45
abcdefghi -> -1
Thank you! (12 Replies)
Hi,
I need help to sort a file contents.
I am using sort -r option to basically reverse the comparison in descending order. However, i found out that my file is not sorted according, can anyone please help.
My data is something like:-
Hello world
20.982342864 343
19.234355545 222... (5 Replies)
Dear Unix Gurus,
I have a list of files that I want to loop over....for example:
sl40_z11.70.txt
sl41_z11.40.txt
sl42_z11.10.txt
sl43_z10.80.txt
using the script
#!/bin/sh
#
echo -n "....enter first Z-coordinate position....."; read zpos
q="scale=3; $zpos"
p=0.3
#... (7 Replies)
Hi Everyone,
I have:
$val="QQ3_1899_CD4".
The output will be:
1899.
I did $val =~ /(\d+)/g; the output is 318994, then i use substr to get those 1899. This is not efficient.
Is any simple way, like just one line can do? Thanks (1 Reply)
Hi,
I want to display the string value with number value. I dont know how to display. Can anyone help me.
This is my code
export A=${file_name}
echo $a $b $sum | awk '{ printf "%011.f,%014.f,%014.f\n", $1,$2,$3}' >> ${MRR_OUTPUT}
the out put shold be
${A}, $a, $b
filename,... (2 Replies)
Hello Everyone,
i have quick question.
I have file names like: bin_map300.asc and I would like to extract grid300.
My approach so far:
name=bin_map300.asc
echo ${name%%.*}
echo ${name##*_}
I am stuck combining the two.
Any help would be appreciated. (3 Replies)
Hi all,
I'm a new programmer to shell script... and I have no idea how to use substring.
I want to extract the numbers from the following string and place it into a variable:
"170 unique conformations found"
The numbers can be more than three digits depending on the case. I just want to... (10 Replies)
I am writing a bash script on ubuntu11.10
I have some string having numbers and letter and want to add all the numbers together
For example
1s2d23f
I want to perform
1 + 2 + 23 and store it in a variable (3 Replies)
Hi,
I am having contents in a file like below,
cat testfile
rpool/swap
rpool/swap14
rpool/swap2
rpool/swap3
I want to sort the above contents like,
rpool/swap
rpool/swap2
rpool/swap3
rpool/swap14
I have tried in this way, (7 Replies)
Discussion started by: Sumanthsv
7 Replies
LEARN ABOUT REDHAT
fifo
FIFO(4) Linux Programmer's Manual FIFO(4)NAME
fifo - first-in first-out special file, named pipe
DESCRIPTION
A FIFO special file (a named pipe) is similar to a pipe, except that it is accessed as part of the file system. It can be opened by multi-
ple processes for reading or writing. When processes are exchanging data via the FIFO, the kernel passes all data internally without writ-
ing it to the file system. Thus, the FIFO special file has no contents on the file system, the file system entry merely serves as a refer-
ence point so that processes can access the pipe using a name in the file system.
The kernel maintains exactly one pipe object for each FIFO special file that is opened by at least one process. The FIFO must be opened on
both ends (reading and writing) before data can be passed. Normally, opening the FIFO blocks until the other end is opened also.
A process can open a FIFO in non-blocking mode. In this case, opening for read only will succeed even if noone has opened on the write side
yet; opening for write only will fail with ENXIO (no such device or address) unless the other end has already been opened.
Under Linux, opening a FIFO for read and write will succeed both in blocking and non-blocking mode. POSIX leaves this behaviour undefined.
This can be used to open a FIFO for writing while there are no readers available. A process that uses both ends of the connection in order
to communicate with itself should be very careful to avoid deadlocks.
NOTES
When a process tries to write to a FIFO that is not opened for read on the other side, the process is sent a SIGPIPE signal.
FIFO special files can be created by mkfifo(3), and are specially indicated in ls -l.
SEE ALSO mkfifo(3), mkfifo(1), pipe(2), socketpair(2), open(2), signal(2), sigaction(2)Linux Man Page 1999-06-20 FIFO(4)