Google Map has APIs. But the requirement is that the Map image should be static and uploaded to the website only. No request or dependency on Google’s website should be needed so that the website can run without Internet. Is it possible or allowed (like a screenshot of the Google Map)? If not, any suggestions
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How to check last boot’s systemd journal log in CentOS 7 Linux?
Posted onThe command to check last boot’s journal log shows nothing on CentOS 7: # journalctl -b -1 Failed to look up boot -1: No such boot ID in journal Is the log stored and where it is? The reason this happens on CentOS 7 is that CentOS 7 by default does not enable the persistent
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How to force systemd to refresh or reloaded a changed fstab on Linux?
Posted onOn Linux, how to force systemd to refresh or reloaded a changed /etc/fstab file? To force systemd to reload the changed /etc/fstab file content, run $ sudo systemctl daemon-reload To, further, make systemd auto remount any new entries, do $ sudo systemctl restart remote-fs.target local-fs.target
How to find the hostname of an IP using /etc/hosts if it has the mapping on Linux?
Posted onCommon DNS queries like ping will first get the IP of a hostname if it exists in /etc/hosts. How to find the hostname of an IP using /etc/hosts if it has the mapping on Linux? Multiple tools on Linux can do the “reverse” checking using /etc/hosts file. For example, if we have a line 192.0.2.1
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Which filesystem operations in HDFS is atomic?
Posted onAtomicity is a very important and fundamental property aspect of filesystems. Applications semantics and many functions depend on and only be available based on the atomicity models of the underlying filesystem. Which filesystem operations in HDFS is atomic? So that locks can be implemented on top of it. In a reasonably widely usable filesystem, some
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How to compare date in SQL?
Posted onHow to compare date in SQL? For example, the ‘users’ table has a column ‘loggin’ which is the date and time. How to find out the ‘users’ whose ‘loggin’ date is later than Jan 10, 2017? In SQL, dates can be compared using ‘’, ‘=‘. For the example described, the SQL statement could be: SELECT
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How to show N entries in result of a select SQL query to MySQL?
Posted onHow to show only N entries in the result of a select SQL query to MySQL? The select SQL query is: select * from qa_users; To limit the N entries (say N = 10), we can use the limit clause as follows. SELECT * FROM qa_users LIMIT 10; Note that it is for MySQL. For
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How to print a line to STDERR and STDOUT in Perl?
Posted onIn Perl, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In Perl, to nicely print a new line to STDOUT, you can use the “say” feature which “Just like print, but implicitly appends a newline”:
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How to print a line to STDERR and STDOUT in OCaml?
Posted onIn OCaml, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In OCaml, you may print a string with the end line character to STDOUT using the function in the Pervasives module: val print_endline : string
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How to print a line to STDERR and STDOUT in C++?
Posted onIn C++, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In C++, you may print the string and then ‘n’ or std::endl to STDOUT by operating on the std::cout stream: std::cout << your_string << std::endl;
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How to print a line to STDERR and STDOUT in PHP?
Posted onIn PHP, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In PHP, you may print a line to STDOUT using echo by appending the PHP_EOL to the string: echo $your_msg . PHP_EOL; For example, $
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How to print a line to STDERR and STDOUT in C?
Posted onIn C, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In C, to print to STDOUT, you may do this: printf(“%sn”, your_str); For example, $ cat t.c #include <stdio.h> void main() { printf(“%sn”, “hello world!”);
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How to print a line to STDERR and STDOUT in Java?
Posted onIn Java, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In Java, you can print string in a new line by ‘System.out.println()’ to STDOUT: System.out.println(“my msg here”); In Java, print a string str to STDERR
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How to print a line to STDERR and STDOUT in Go?
Posted onIn Go, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In Go, you can use the ‘Println()’ func from the ‘fmt’ package to print a line to STDOUT: import(“fmt”) fmt.Println(“my msg here”) In Go, os.Stderr
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Printing a Line to STDERR and STDOUT in Python
Posted onIn Python, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In Python, to print a string str with a new line to STDOUT: print str In Python to print a line to STDERR: import sys
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How to print a line to STDERR and STDOUT in Bash?
Posted onIn Bash, how to print a string as a line to STDOUT? That is, the string and the newline character, nicely? And similarly, how to print the line to STDERR? In Bash, you can simply use the echo command: echo “your message here” or echo your message here Examples: $ echo the message here the
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How to get the running process’ parent process’ ID in C / C++?
Posted onHow to get the running process’ parent process’ ID in C / C++? In C and C++, you can call the getppid() library function which is a function from the POSIX library. #include <sys/types.h> #include <unistd.h> pid_t getppid(void); getppid() returns the process ID of the parent of the calling process. Example usage: getppid.c #include <stdio.h>
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How to get the running process’ parent process’ ID in Go?
Posted onHow to get the running process’ parent process’ ID in Go? In Go, you may call the os.Getppid() func from the os package to get the parent process’ pid. func Getppid() int Getppid returns the process id of the caller’s parent. One example is as follows. $ gore gore version 0.2.6 :help for help gore>
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How to get the running process’ parent process’ ID in Python?
Posted onHow to get the running process’ parent process’ ID in Python? In Python, you can get the parent process’ pid by calling os.getppid(): import os ppid = os.getppid() One example: The shell’s pid: $ echo $$ 21779 Start a python REPL and get its parent pid (the shell’s): $ python Python 2.7.5 (default, Nov 6
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How to get the running process’ parent process’ ID in Bash?
Posted onHow to get the running process’ parent process’ ID in Bash? In Bash, you can get the parent process’s pid from the variable PPID. Note that in a (…) subshell, the $$ stores the subshell’s parent shell pid actually.