I am having a trivial doubt. Please see the below pipeline code sequence.
Code:
command1 | (command 2; commend 3)
I am aware that the command that follows pipe will run in the sub shell by the Unix kernel. But how about here? Since these set of commands are grouped under "parantheses", will they run inside another sub shell of pipe's shell? Hope my question is not so be-wilder to be answered
Last edited by royalibrahim; 01-20-2010 at 02:33 PM..
can we use pipes to redirect the output of any command to grep .....
like i wanted to write this script about checking the online status of a certain user so ...can i send the output of who to grep directly using pipes...
one way was this :
who > temp
grep $uname temp
i was wondering if... (4 Replies)
Hi All
Here i have a piece of code,
set filename "./GopiRun.sh"
#I need to wait here until the GopiRun.sh is completed how do i achive this
exit. (1 Reply)
Hi Guys,
Just a question about subprocesses.. Lately one of our servers has started to throw out the following error:
SYSTEM ERROR: Too many subprocesses, cannot fork. Errno=12
We've already increased the threshold twice. Its now up to 8000 and the swap space has also been increased. We... (6 Replies)
Hi,
I am trying to run a shell script using subprocess in python.
I can run simple script with arguments using subprocess.But I am not able to embed xterm in subrocess command.
#!/usr/bin/python
import subprocess
subprocess.call()
Above code gives me error.
Please help me in... (2 Replies)
Hi guys,
I'm learning python and perl and i was trying to run from python a perl script using the subprocess module.
I have an issue that i don't understand regarding this.
I run this code:
#!/usr/bin/python
import subprocess
p2 = subprocess.Popen(,stdout=subprocess.PIPE)
output2 =... (2 Replies)
After struggling with this for days now, I'm reaching out to the experts of all things linux for some help with this.
I'm trying to run the following working command (on command line) inside a python script using subprocess:
rsync -avzh --no-perms --delete --include="*sub*" --exclude='*'... (2 Replies)
So I have this basic script, see below
import subprocess
import shlex
command = "gcloud projects list"
subprocess.check_output(shlex.split(command))
subprocess.check_call(shlex.split(command))
The subprocess.check_call(shlex.split(command)) actually return what I expect. It returns... (6 Replies)
Discussion started by: scj2012
6 Replies
LEARN ABOUT V7
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)
01-19-2010
