10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Hi all,
While doing some checks I found a kind of interesting arithmetic factorial chart with sed, sharing this may be simple but thought to share,
# n=20;for i in `seq $n`;do printf "`seq $i|xargs|sed 's/ /*/g'`= ";echo "`seq $i|xargs|sed 's/ /*/g'`"| bc;done
1= 1
1*2= 2
1*2*3= 6... (6 Replies)
Discussion started by: rveri
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2. Shell Programming and Scripting
Hi Guru's.
I am trying to use to check if $5 is greater than 80 & if not 100, then to print $0 :
awk '{ if ($5>80) && if ($5 != 100) print $0}
But getting error:
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syntax error The source line is 1.
The error... (6 Replies)
Discussion started by: rveri
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Hi guys
Quick question
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Hello all,
Quick question from a fairly new to Unix developer.
if
then
completedLogFile=$logfile.$(date +%Y%m%d-%H:%M:%S)
mv $logfile $completedLogFile
fi
I understand that this portion of code is simply copying a tmp logfile to a completed logfile when a condition is true. The... (2 Replies)
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5. UNIX for Dummies Questions & Answers
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Hi,
Is there a simple way, using ksh, to find the byte position in a file that a stated character appears?
Many thanks
Helen (2 Replies)
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7. Shell Programming and Scripting
Hi i just wanted to know is there anyway to log the keystrokes on a remote computer? For example i let my nieces play on my other computer downstairs *my computer and the one downstairs are on a LAN* and i want to see everything they type in to make sure they arent doing anything they are supposed... (1 Reply)
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8. UNIX for Dummies Questions & Answers
Hi, I am new to UNIX, and am learning from this tutorial : http://www.ee.surrey.ac.uk/Teaching/Unix/index.html
It keeps telling me to files downloaded from the internet (like .txt files) to the directory, and I dont know how to.
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9. UNIX for Dummies Questions & Answers
Hello There!
I am trying to write this SIMPLE script in Bourne Shell but I keep on getting syntax errors. Can you see what I am doing wrong? I've done this before but I don't see the difference. I am simply trying to take the day of the week from our system and when the teachers sign on I want... (7 Replies)
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10. UNIX for Dummies Questions & Answers
I know in DOS, when you want to pull up your last/previous command, you hit the up/down arrows. How do you do that with UNIX? (3 Replies)
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ASSERT_PERROR(3) Linux Programmer's Manual ASSERT_PERROR(3)
NAME
assert_perror - test errnum and abort
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <assert.h>
void assert_perror(int errnum);
DESCRIPTION
If the macro NDEBUG was defined at the moment <assert.h> was last included, the macro assert_perror() generates no code, and hence does
nothing at all. Otherwise, the macro assert_perror() prints an error message to standard error and terminates the program by calling
abort(3) if errnum is nonzero. The message contains the filename, function name and line number of the macro call, and the output of str-
error(errnum).
RETURN VALUE
No value is returned.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
+----------------+---------------+---------+
|Interface | Attribute | Value |
+----------------+---------------+---------+
|assert_perror() | Thread safety | MT-Safe |
+----------------+---------------+---------+
CONFORMING TO
This is a GNU extension.
BUGS
The purpose of the assert macros is to help programmers find bugs in their programs, things that cannot happen unless there was a coding
mistake. However, with system or library calls the situation is rather different, and error returns can happen, and will happen, and
should be tested for. Not by an assert, where the test goes away when NDEBUG is defined, but by proper error handling code. Never use
this macro.
SEE ALSO
abort(3), assert(3), exit(3), strerror(3)
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/.
GNU
2017-09-15 ASSERT_PERROR(3)