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Full Discussion: False positive grep?
Top Forums Shell Programming and Scripting False positive grep? Post 303045948 by sea on Sunday 19th of April 2020 03:33:38 AM
Old 04-19-2020
Good morning MIG Smilie

Yes, I'm always getting confused whether to use /dev/null or /dev/zero, because most of the *nix flavors I use, have both.

Code:
if [[ ${#NUM} -ge 0 ]] &2>/dev/null

Yes, this might be unususal, but it helps to avoid parsing errors -> well the visual breakup <- when 'catching' arrow keys (NOT specificly).

Are you refering to the other '^[[' line just above - which is commented out, or to the '[a-zA-Z]' grep to be changed to ~=?
But basicly, neither of those lines are 'now' executed, because it's 'all' left out anyway - to my understanding - the only reason it's still there, is because I just had it rewritten it compared to the initial post (before sleeping).
Code:
			else
				# It's not a number, catch other cases
				continue
			# Actualy, all checks below are (can be) left out....

Or am I missing a point of yours?
Thank you.
 

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MEM(4)                                                       Linux Programmer's Manual                                                      MEM(4)

NAME
mem, kmem, port - system memory, kernel memory and system ports DESCRIPTION
/dev/mem is a character device file that is an image of the main memory of the computer. It may be used, for example, to examine (and even patch) the system. Byte addresses in /dev/mem are interpreted as physical memory addresses. References to nonexistent locations cause errors to be returned. Examining and patching is likely to lead to unexpected results when read-only or write-only bits are present. Since Linux 2.6.26, and depending on the architecture, the CONFIG_STRICT_DEVMEM kernel configuration option limits the areas which can be accessed through this file. For example: on x86, RAM access is not allowed but accessing memory-mapped PCI regions is. It is typically created by: mknod -m 660 /dev/mem c 1 1 chown root:kmem /dev/mem The file /dev/kmem is the same as /dev/mem, except that the kernel virtual memory rather than physical memory is accessed. Since Linux 2.6.26, this file is available only if the CONFIG_DEVKMEM kernel configuration option is enabled. It is typically created by: mknod -m 640 /dev/kmem c 1 2 chown root:kmem /dev/kmem /dev/port is similar to /dev/mem, but the I/O ports are accessed. It is typically created by: mknod -m 660 /dev/port c 1 4 chown root:kmem /dev/port FILES
/dev/mem /dev/kmem /dev/port SEE ALSO
chown(1), mknod(1), ioperm(2) COLOPHON
This page is part of release 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. Linux 2015-01-02 MEM(4)
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