Here is an example code that shows the issue I have:
If I understand it correctly, "head" finishes on the first match (as expected), but "grep" is not aware of it until it tries to write the next line (the second match). When it does, it finds out the pipe is closed so it also finishes.
That's normally not a problem, but if you have an infinite input stream containing only one match, it won't never stop. Any solution?
Hi Everyone
I am building some A Class HP boxes as web proxy servers, have just installed HP-UX 11.00 and am starting to configure one according to our standard build policy.
However on the A Class I just happened to place the software depot this error message keeps popping up every 2 mins:
... (1 Reply)
I have written the following program. The function of this prog is to read data from a file(source.c) and write into another file(dest.c) using pipes. I have just written a line in the source file.Im able to compile and run the program without errors. But the data is not written onto the other... (2 Replies)
hi all,
this is how my scrip looks like
#!/bin/sh
bindir='/opt/apps/script/bin'
datadir='/opt/apps/script/data'
dir='/opt/apps/script'
while : ; do
ls -1rt /opt/apps/script/data/check.txt*|tail -1 > /dev/null 2>&1
if ;then
chmod +rwx $bindir/dummy2.sh
... (8 Replies)
Hi all,
I tried the following command
$ find / -name xyx | ls -l
so logically it should show the listing of directory xyz , assuming there's only one instance of xyz . But the above command shows the listing of current directory instead.
I got the desired result using it in the... (4 Replies)
Hello Everybody,
thanks in advance for spending some time in my problem.
My problem is this:
I want to call a java-Programm out of my shell skript, check if die return code is right, and split the output to the normal output and into a file.
The following code doesn't work right, because in... (2 Replies)
I want to have a message send & receive through 2 half-duplex pipes
Flow of data
top half pipe
stdin--->parent(client) fd1--->pipe1-->child(server) fd1
bottom half pipe
child(server) fd2---->pipe2--->parent(client) fd2--->stdout
I need to have boundary structed message... (1 Reply)
Hi!
I'm having problems with pipes... I need comunnications with childs processes and parents, but only one child can comunnicate with parent (first child), others childs can't.
A brief of code:
if(pipe(client1r)<0){
perror("pipe");
}
... (1 Reply)
1. The problem statement, all variables and given/known data:
My problem is an infinite loop when i press any other key other then Y or y in the while loop. what i want it to do is return to the normal script outside of it if pressing N or n or keep asking the same question if its any other... (4 Replies)
Discussion started by: Ren_kun
4 Replies
LEARN ABOUT DEBIAN
bup-margin
bup-margin(1) General Commands Manual bup-margin(1)NAME
bup-margin - figure out your deduplication safety margin
SYNOPSIS
bup margin [options...]
DESCRIPTION
bup margin iterates through all objects in your bup repository, calculating the largest number of prefix bits shared between any two
entries. This number, n, identifies the longest subset of SHA-1 you could use and still encounter a collision between your object ids.
For example, one system that was tested had a collection of 11 million objects (70 GB), and bup margin returned 45. That means a 46-bit
hash would be sufficient to avoid all collisions among that set of objects; each object in that repository could be uniquely identified by
its first 46 bits.
The number of bits needed seems to increase by about 1 or 2 for every doubling of the number of objects. Since SHA-1 hashes have 160 bits,
that leaves 115 bits of margin. Of course, because SHA-1 hashes are essentially random, it's theoretically possible to use many more bits
with far fewer objects.
If you're paranoid about the possibility of SHA-1 collisions, you can monitor your repository by running bup margin occasionally to see if
you're getting dangerously close to 160 bits.
OPTIONS --predict
Guess the offset into each index file where a particular object will appear, and report the maximum deviation of the correct answer
from the guess. This is potentially useful for tuning an interpolation search algorithm.
--ignore-midx
don't use .midx files, use only .idx files. This is only really useful when used with --predict.
EXAMPLE
$ bup margin
Reading indexes: 100.00% (1612581/1612581), done.
40
40 matching prefix bits
1.94 bits per doubling
120 bits (61.86 doublings) remaining
4.19338e+18 times larger is possible
Everyone on earth could have 625878182 data sets
like yours, all in one repository, and we would
expect 1 object collision.
$ bup margin --predict
PackIdxList: using 1 index.
Reading indexes: 100.00% (1612581/1612581), done.
915 of 1612581 (0.057%)
SEE ALSO bup-midx(1), bup-save(1)BUP
Part of the bup(1) suite.
AUTHORS
Avery Pennarun <apenwarr@gmail.com>.
Bup unknown-bup-margin(1)