The code you posted has a problem. But even if you solve that problem, there is another one. fork() dup()licates fd's from the parent but if you don't have some kind of synchronous read between the childs, you'll have unexpected results.
Do you really want to use multiple processes to read the same fd?
Try running this several times to see what I'm talking about:
Ok, I'm sure this is a total newbie question, but I think I'm in the right place, no?
I'm trying to call a perl module from a cgi script - Mail::Sendmail - and my web host installed the module in a directory that doesn't seem to be accessible, at least not the way I'm trying. But I thought you... (1 Reply)
I am trying to find a way to check the current status of a file. Such as some cron job processes are dependent on the completion of others. if a file is currently being accessed / modified or simply open state I will wait until it is done being processed before attempting the next process on that... (3 Replies)
Im working on writing a small operating system. I am currently working on implementing dup, dup2, pipe, and close and I need to implement some type of file descriptor table in my PCB.
I was wondering if there is anyone who is familiar with linux/unix implementation of these tables who could... (6 Replies)
Hello All,
Im opening a file desciptor in perl and sending data using print CMD "$xyz".
is there a limit to the length of the string that I can give to this CMD at a time. (3 Replies)
Hello,
How can i use file descriptor in a script to read 2 files at the same time and extract line 200 from file 1 and line 500 from file 2.
Thanks. (6 Replies)
Hello guys!
I had seen some posts at this forum talking about my problem, but maybe my scenario is a little different, and I want other solutions.
I saw users of this forums saying that the way to shared sockets is using UNIX Sockets, but this is the only way in my scenario?
My Scenario:... (4 Replies)
I am trying to write a script which will only show me the file descriptor count for a process/pid. My script will return me the count only not the whole output. For example, I would like my script to return the output 23 this case, not the whole output.
Can anybody please help me how do I get... (11 Replies)
Hi,
I am trying to read a file line-by-line in a while loop, and perform some tasks which involves non-interactive SSH to a remote server. The code looks something like this --
#!/usr/bin/ksh
export myFile=/path/to/my/file.load
while read line
do
do something
## Adding the SSH... (2 Replies)
Discussion started by: Subu1987
2 Replies
LEARN ABOUT MINIX
ppmtosixel
ppmtosixel(1) General Commands Manual ppmtosixel(1)NAME
ppmtosixel - convert a portable pixmap into DEC sixel format
SYNOPSIS
ppmtosixel [-raw] [-margin] [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces sixel commands (SIX) as output. The output is formatted for color printing, e.g. for a DEC
LJ250 color inkjet printer.
If RGB values from the PPM file do not have maxval=100, the RGB values are rescaled. A printer control header and a color assignment table
begin the SIX file. Image data is written in a compressed format by default. A printer control footer ends the image file.
OPTIONS -raw If specified, each pixel will be explicitly described in the image file. If -raw is not specified, output will default to com-
pressed format in which identical adjacent pixels are replaced by "repeat pixel" commands. A raw file is often an order of magni-
tude larger than a compressed file and prints much slower.
-margin
If -margin is not specified, the image will be start at the left margin (of the window, paper, or whatever). If -margin is speci-
fied, a 1.5 inch left margin will offset the image.
PRINTING
Generally, sixel files must reach the printer unfiltered. Use the lpr -x option or cat filename > /dev/tty0?.
BUGS
Upon rescaling, truncation of the least significant bits of RGB values may result in poor color conversion. If the original PPM maxval was
greater than 100, rescaling also reduces the image depth. While the actual RGB values from the ppm file are more or less retained, the
color palette of the LJ250 may not match the colors on your screen. This seems to be a printer limitation.
SEE ALSO ppm(5)AUTHOR
Copyright (C) 1991 by Rick Vinci.
26 April 1991 ppmtosixel(1)