10-05-2018
Quote:
Originally Posted by
woodson2
I'm having an issue with bash read input when using a case statement.
The script halts and doesn't read the input on the first loop.
There is just one loop, and it looks like the first read (outside the loop) has completed accepting the preset value "8hrs" as <return> was hit.
Quote:
if I hit enter then the scripts starts to respond as expected.
. . .
Which is the correct behaviour of
read - read a line terminated by a return character.
Quote:
script sits here and doesn't read the given defaultans above.
There are no modifiers / options for this (second)
read - no default value, no timeout value, no char count - so, yes, it sits there and waits for your input, terminated by a <Return>.
Last edited by RudiC; 10-05-2018 at 06:42 PM..
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LEARN ABOUT XFREE86
ppmtopgm
ppmtopgm(1) General Commands Manual ppmtopgm(1)
NAME
ppmtopgm - convert a portable pixmap into a portable graymap
SYNOPSIS
ppmtopgm [ppmfile]
DESCRIPTION
Reads a portable pixmap as input. Produces a portable graymap as output. The output is a "black and white" rendering of the original
image, as in a black and white photograph. The quantization formula used is .299 r + .587 g + .114 b.
Note that although there is a pgmtoppm program, it is not necessary for simple conversions from pgm to ppm , because any ppm program can
read pgm (and pbm ) files automatically. pgmtoppm is for colorizing a pgm file. Also, see ppmtorgb3 for a different way of converting
color to gray. And ppmdist generates a grayscale image from a color image, but in a way that makes it easy to differentiate the original
colors, not necessarily a way that looks like a black and white photograph.
QUOTE
Cold-hearted orb that rules the night
Removes the colors from our sight
Red is gray, and yellow white
But we decide which is right
And which is a quantization error.
SEE ALSO
pgmtoppm(1),ppmtorgb3(1),rgb3toppm(1),ppmdist(1),ppm(5),pgm(5)
AUTHOR
Copyright (C) 1989 by Jef Poskanzer.
10 April 2000 ppmtopgm(1)