For the purpose of providing a web service to a Node.js project to users, we may require a small middleware to start an HTTP service to handle the HTTP requests.
The default file upload size is 2M.
If we are supposed to increase the size, a few update would be required.
SSH port forwarding is a mechanism in SSH for tunneling application ports from the client machine to the server machine, or vice versa.
If we wish to visit a port in remote but behind the firewall, we can use SSH port forwarding to bind that port into local.
This post lists a few examples to check the status of your system in macOS and Linux
In general, we can click File->Export Settings to export your configuration from one application belong to another belong to JetBrain. If we have multiple workspace distributed in our laptop and PC in our lab, we can even use some plugin like Settings Repository to synchronize the configurations automatically. Read more
Sometimes, we are supposed to accept uncertain number of arguments in C++.
In this post, I am going to introduce 3 ways to implement it, so that you can pick up one of them which is most fit for you in current situation.
Signal plays an important role in communication with POSIX system.
For example, what if our code been killed, interrupted, hung on? Generally, the operation system (I am talking about BSD, Unix-like, POSIX system, same in the follow but will omitted), will not really "KILL" it, it will just send a kill signal with id to this process, the this process will process this signal later.
Here is a table to describe the id to default action.
Recently, when I ran "yum update" for some update, which will get an error as follow:
--> Processing Dependency: libstdc++.so.6 for package: pcre-8.32-17.el7.i686 ---> Package zlib.i686 0:1.2.7-17.el7 will be installed --> Running transaction check ---> Package libcap-ng.i686 0:0.7.5-4.el7 will be installed ---> Package libstdc++.i686 0:4.8.5-16.el7 will be installed --> Finished Dependency Resolution Error: Multilib version problems found. This often means that the root cause is something else and multilib version checking is just pointing out that there is a problem. Eg.: 1. You have an upgrade for libstdc++ which is missing some dependency that another package requires. Yum is trying to solve this by installing an older version of libstdc++ of the different architecture. If you exclude the bad architecture yum will tell you what the root cause is (which package requires what). You can try redoing the upgrade with --exclude libstdc++.otherarch ... this should give you an error message showing the root cause of the problem. 2. You have multiple architectures of libstdc++ installed, but yum can only see an upgrade for one of those architectures. If you don't want/need both architectures anymore then you can remove the one with the missing update and everything will work. 3. You have duplicate versions of libstdc++ installed already. You can use "yum check" to get yum show these errors. ...you can also use --setopt=protected_multilib=false to remove this checking, however this is almost never the correct thing to do as something else is very likely to go wrong (often causing much more problems). Protected multilib versions: libstdc++-4.8.5-16.el7.i686 != libstdc++-4.8.5-11.el7.x86_64 Error: Protected multilib versions: libgcc-4.8.5-16.el7.i686 != libgcc-4.8.5-11.el7.x86_64 Error: Protected multilib versions: pcre-8.32-17.el7.i686 != pcre-8.32-15.el7_2.1.x86_64 Error: Protected multilib versions: elfutils-libelf-0.168-8.el7.i686 != elfutils-libelf-0.166-2.el7.x86_64 Error: Protected multilib versions: libcap-2.22-9.el7.i686 != libcap-2.22-8.el7.x86_64 Error: Protected multilib versions: libdb-5.3.21-20.el7.i686 != libdb-5.3.21-19.el7.x86_64 Error: Protected multilib versions: libgcrypt-1.5.3-14.el7.i686 != libgcrypt-1.5.3-13.el7_3.1.x86_64 Error: Protected multilib versions: elfutils-libs-0.168-8.el7.i686 != elfutils-libs-0.166-2.el7.x86_64 Error: Protected multilib versions: nss-softokn-freebl-3.28.3-8.el7_4.i686 != nss-softokn-freebl-126.96.36.199-14.4.el7.x86_64 Error: Protected multilib versions: libselinux-2.5-11.el7.i686 != libselinux-2.5-6.el7.x86_64