how can i redirect standard input? i dont remember :/, though could you redirec not from a command? i mean, to redirect always stdin and stout (1 Reply)
I tried copy the output files from find command into a directory.
Example,
find / -name core 2>/dev/null | xargs cp????
I have known that we can use xargs to execute command lines from standard input but how to use it in this case.
Or I can do something besides xargs. (2 Replies)
Dear...
I have a scrpit that contains multiple read command.... when I run the script I have to enter 3 variables so that I can get the output..
but, I dont want to put those 3 inputs manually every time... I want to make a shell that reads the 3 inputs from a file.
the script name is... (4 Replies)
So, I have a file that has some duplicate lines. The file has a header line that I would like to keep at the top.
I could do this by extracting the header from the file, 'sort -u' the remaining lines, and recombine them. But they are quite big, so if there is a way to do it with a single... (1 Reply)
Hi,
I have a file with a header line, followed by some contents. How can I sort the file according to header lines?
eg.
/* abcd_005*/
a
bc
/* abcd_001*/
d
e
/* abcd_002*/
x
y
desired output:
/*abcd_001*/ (0 Replies)
Hello,
I am new to scripting.
How do I read multiple lines from the command line?
I know read reads one line, but if I have to read multiple lines, how should I do?
Thanks,
Prasanna (4 Replies)
So, I am new to shell scripting and have a few problems.
I know how to read from standard input but I do not know how to really compare it to say, a character. I am trying to compare it to a character and anything exceeding just a character, the user will get an output message, but the program... (7 Replies)
I have a program that requires the user to enter input values while it is being run
for example in bash
...
...
..
echo "Enter your input"
read input
echo $input
...
...
...I need to schedule this program with crontab, hence a problem, cronjobs run in the background, any ideas on how to... (10 Replies)
Just started learning Unix and received my first assignment recently. We haven't learned many commands and honestly, I'm stumped. I'd like to receive assistance/guidance/hints.
1. The problem statement, all variables and given/known data:
How do I write a shell script that takes in a file or... (4 Replies)
Discussion started by: fozilla
4 Replies
LEARN ABOUT OSF1
ppmhist
ppmhist(1) General Commands Manual ppmhist(1)NAME
ppmhist - print a histogram of a portable pixmap
SYNOPSIS
ppmhist [-hexcolor] [-noheader] [-map] [-nomap] [-sort={frequency,rgb}] [ppmfile]
DESCRIPTION
Reads a PPM image as input. Generates a histogram of the colors in the image, i.e. a list of all the colors and how many pixels of each
color are in the image.
OPTIONS
-sort={frequency,rgb}
The -sort option determines the order in which the colors are listed in the output. frequency means to list them in order of how
pixels in the input image have the color, with the most represented colors first. rgb means to sort them first by the intensity of
the red component of the color, the of the green, then of the blue, with the least intense first.
The default is frequency.
-hexcolor
Print the color components in hexadecimal. Default is decimal.
-noheader
Do not print the column headings.
-map Generates a PPM file of the colormap for the image, with the color histogram as comments.
-nomap Generates the histogram for human reading. This is the default.
SEE ALSO ppm(5), pgmhist(1), ppmtomap(1), pnmhistmap(1), ppmchange(1)AUTHOR
Copyright (C) 1989 by Jef Poskanzer.
17 September 2000 ppmhist(1)