Page 5 – BEAUTY AND PLAY

Valavil RESEARCH: BLOG

How to use bash builtin command named “readonly” ?

ABOUT readonly Marks name specified by Name parameter as read-only. TYPICAL COMMANDLINE SESSION [bash] $a=1 $a=2 $echo $a 2 $readonly a $a=1 bash: a: readonly variable $echo $a 2 $a=2 bash: a: readonly variable $ [/bash] LINK https://www.ibm.com/support/knowledgecenter/ssw_aix_72/com.ibm.aix.osdevice/bourne_shell_builtin_cmd_list.htm

January 28, 2019
About bash builtin command named “eval”

ABOUT eval eval is a builtin command of the Bash shell. It concatenates its arguments into a single string, joining the arguments with spaces, then executes that string as a bash command. It’s similar to running bash -c “string”, but eval executes the command in the current shell environment rather than creating a child shell…

December 22, 2018
A bash builtin command named “enable” to enable or disable a bash builtin command

[bash light=”true”] $command $echo $? 0 $enable -n command $command bash: command: command not found $echo $? 127 $enable command $command $enable -n enable $enable bash: enable: command not found $ [/bash] RELATED SOURCE CODE EXPOSURE [c light=”true”] /* Enable/disable shell commands present in LIST. If list is not specified, then print out a list…

November 22, 2018
Get the hang of dbus-monitor command from dbus debian package

[bash light=”true”] $dbus-monitor –session –profile | tee dbus-monitor-profile.txt #type timestamp serial sender destination path interface member # in_reply_to sig 1542567372.723960 2 org.freedesktop.DBus :1.3693 /org/freedesktop/DBus org.freedesktop.DBus NameAcquired sig 1542567372.723980 4 org.freedesktop.DBus :1.3693 /org/freedesktop/DBus org.freedesktop.DBus NameLost sig 1542567373.088315 5 org.freedesktop.DBus :1.3692 /org/freedesktop/DBus org.freedesktop.DBus NameLost sig 1542567373.088350 3737 org.freedesktop.DBus <none> /org/freedesktop/DBus org.freedesktop.DBus NameOwnerChanged sig 1542567373.088364 6 org.freedesktop.DBus :1.3692…

November 18, 2018
Learning D-Bus

https://www.freedesktop.org/wiki/Software/dbus/ https://www.freedesktop.org/wiki/IntroductionToDBus/ https://www.packtpub.com/mapt/book/application_development/9781849519427/10/ch10lvl1sec126/time-for-action–listening-to-d-bus https://dbus.freedesktop.org/doc/dbus-specification.html https://stackoverflow.com/questions/2830858/controlling-gnome-volume-using-dbus https://dbus.freedesktop.org/doc/dbus-tutorial.html#concepts https://dbus.freedesktop.org/doc/diagram.svg https://developer.gnome.org/NetworkManager/stable/spec.html https://developer.gnome.org/NetworkManager/stable/gdbus-org.freedesktop.NetworkManager.html http://www.beautifulwork.org/wp-content/uploads/2018/11/dbus.pdf http://www.beautifulwork.org/wp-content/uploads/2018/11/dbus.docx

November 8, 2018
Meaning of a function wrapper in python exposure

http://wiki.c2.com/?FunctionWrapper https://wiki.python.org/moin/FunctionWrappers

November 6, 2018
a look into the bash builtin command named “disown”

[bash light=”true”] $jobs -l $ping gnu.org PING gnu.org (208.118.235.148) 56(84) bytes of data. 64 bytes from wildebeest.gnu.org (208.118.235.148): icmp_seq=1 ttl=53 time=267 ms 64 bytes from wildebeest.gnu.org (208.118.235.148): icmp_seq=2 ttl=53 time=266 ms 64 bytes from wildebeest.gnu.org (208.118.235.148): icmp_seq=3 ttl=53 time=267 ms 64 bytes from wildebeest.gnu.org (208.118.235.148): icmp_seq=4 ttl=53 time=321 ms 64 bytes from wildebeest.gnu.org (208.118.235.148): icmp_seq=5…

November 4, 2018
Hacking with Makefile for machine architecture detection

# SPDX-License-Identifier: GPL-2.0 INCLUDEDIR := -I. CFLAGS := $(CFLAGS) $(INCLUDEDIR) -Wall -O2 -g TEST_GEN_FILES := adi-test UNAME := $(shell uname -m) all: $(TEST_GEN_FILES) $(TEST_GEN_FILES): adi-test.c ifeq ($(UNAME), sparc64) $(info Machine architecture does match) else $(info exit) $(error Machine architecture does not match) endif TEST_PROGS := drivers_test.sh include ../../lib.mk $(OUTPUT)/adi-test: adi-test.c

November 1, 2018
Command for PHP information and configuration

[php] $php –info phpinfo() PHP Version => 7.3.0RC3 System => Linux debian 4.17.0-3-amd64 #1 SMP Debian 4.17.17-1 (2018-08-18) x86_64 Build Date => Oct 15 2018 09:53:04 Server API => Command Line Interface Virtual Directory Support => disabled Configuration File (php.ini) Path => /etc/php/7.3/cli Loaded Configuration File => /etc/php/7.3/cli/php.ini Scan this dir for additional .ini files…

October 16, 2018
Look into bash builtin command named typeset

$typeset -n gree=55 bash: typeset: 55′: invalid variable name for name reference $typeset -n 55=gree bash: typeset:55=gree’: not a valid identifier$typeset -n gree=pwd$echo $gree $echo $pwd $typeset -n vary=$?bash: typeset: `0′: invalid variable name for name reference$typeset vary=$?$echo $vary1$echo $vary1$echo $?0$echo $vary1$echo varyvary$echo $vary1$echo $vary1$echo $?0$typeset vary=$?$echo $vary0$ $typeset hello $echo $hello $echo $? 0…

October 7, 2018