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Full Discussion: Questions about file descriptors
Top Forums Shell Programming and Scripting Questions about file descriptors Post 302917497 by Don Cragun on Wednesday 17th of September 2014 05:49:02 AM
Old 09-17-2014
Hi gull04,
Settings in syslog.conf affect where messages printed by syslog go; not where messages printed by echo go.

Hi solaris_user,
From what you have shown us, the word stdout should have appeared in the file named out and the word stderr should have appeared on your terminal's screen unless you had an earlier exec statement in your shell redirecting file descriptor 2 to another file or you redirected the file descriptor 2 output of the shell script containing the statements you showed us to another file.

If you wanted both stdout and stderr from your subshell to be saved in the file named out you would need soething like:
Code:
{ echo "stdout" >&1; echo "stderr" >&2; } 2>&1 > out

I assume that you already know that >&1 is shorthand notation for 1>&1 which redirects the output directed to file descriptor 1 to be written to file descriptor 1 (which is a no-op), so the code shown in red above can be deleted without affecting the results.
This User Gave Thanks to Don Cragun For This Post:
solaris_user
 

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LEARN ABOUT DEBIAN

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)
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