Csh - the C Shell Check out my other tutorials on the Unix Page, and my Check my blog. Copyright 1. 99. 4, 1. ![]() In Windows NT Operating systems, I tried to add this directory to my system PATH environment variable: C:\xampp\php So I added that directory by "My Computer. Having a system backup is always useful, especially if your system gets corrupt or damaged. Although system backup is a great feature, it can sometimes fail to work. While the Windows command line is not considered as powerful as a Linux's, here are some Windows command line tips and tricks not everyone might know about. Deploy Windows 10 in a test lab using System Center Configuration Manager. ![]() Bruce Barnett and General Electric Company. Copyright 2. 00. 1, 2. Bruce Barnett. All rights reserved. You are allowed to print copies of this tutorial for your personal. Original version written in 1. Sun Observer. This section describes C Shell (CSH/TCSH) programming. It covers conditional testing, control loops, and other advanced techniques. This month begins a tutorial on the bad- boy of UNIX, lowest of the low. Yes, I am talking. C shell. FAQ's flame it. Experts have criticized it. Unfortunately, this puts UNIX novices in an awkward. Many people are given the C shell as their default shell. They aren't familiar with it, but they have to learn. They need help, but get criticized every time they ask a question. Imagine the following conversation, initiated by a posting on USENET. Novice: How do I do XYZ using the C shell? Expert: You shouldn't use the C shell. Use the Bourne shell. Novice: I try to, but I get syntax errors. Expert: That's because you are using the C shell. Use the Bourne shell. Novice: I've now using the Bourne shell. How to I create aliases. Bourne shell? Expert: You can't. Novice: I don't have these shells on all of the systems I use. What can I use? Expert: In that case, use the C shell. Novice: But you told me I shouldn't use the C shell!?! Expert: Well, if you have to, you can use the C shell. It's fine for interactive sessions. But you shouldn't use it for scripts. Novice: It's really confusing trying to learn two shells. I don't know either shell very well, and. I'm trying to learn. JUST enough to customize my environment. I'd rather just learn one shell at a time. Expert: Well, it's your funeral. Novice: How do I do XYZ using the C shell? Another Expert: You shouldn't be using the C shell. Use the Bourne shell. Novice: @#%& ! The C shell does have problems. See My top 1. 0 reasons not to use the C shell.). Some can be fixed. Some are unimportant now, but later on might cause grief. I'll mention these problems. But I'll let you decide. C shell, or start using the Bourne shell. Switching shells is difficult. If you want to use the C shell, that's fine. I'll show you the pitfalls, so you can intelligently decide. No pressure. You can switch at any time. But be aware that the C shell is seductive. It does have some advantages over the Bourne shell. But sometimes what seems like an advantage turns into a disadvantage later. Let me discuss them in detail. The first problem I faced with the C shell involved another language. I had a problem that required a. The C shell has a. The following command. C shell. echo "This quote doesn't end. The Bourne shell would continue till the end of the script. This is a good feature for an interactive shell. But if you want to include a multi- line string, such as an. C shell script, you will have problems. You can place a backslash at the end of each line. Using them inside a C shell script would require two backslashes in a row. There are some other strange quoting problems. Like the Bourne shell, the C shell has three ways to quote. You can use the single quote, double quote and backslash. But combine them, and find some strange combinations. You can put anything inside single quotes in a Bourne shell script. The C shell won't let you do that. You have to use a backslash if you want to do this. Also, the following. But in this case you cannot even use a backslash. The followings an error in the C shell. Unix shells have many special characters, and quoting them marks them as normal ASCII - telling the shell not to interpret them. And this is true with every Unix shell there is, except the C shell. In the above cases, putting quotes around some characters. C shell, instead of. The second problem is subtle, but may be the next problem you. The Bourne shell has a true syntax parser: the. Some pieces are commands. Other pieces are quoted strings. File redirection is handled the same way. Commands can be combined on one line, or span several lines. It doesn't matter. As an example, you can use. The parsing of file redirection is independent of the particular command. The following. is valid in the Bourne shell. The same holds true for other Bourne shell commands. Once you learn the principles, the behavior is predictable. The C shell does not have a true parser. Instead, the code executes one section for the. What works for one command may not work for another. C shell. There are two file redirections, and the C shell can't do either. Also, in the C shell, certain words. Therefore you might try something that works with one command. I've reported a lot of bugs to Sun, and to their credit, many have been fixed. Try the same code on other systems, however, and you might get syntax errors. The parsing problem is also true with shell built- in commands. Combine them, and. Try the following C shell sequence. There are other examples of this. These are the types of problems that sneak up on you when you. The Bourne shell has the. You can't do this with the C shell. The C shell seems to act on one line at a time and. Sometimes you have to ask a person for input in the middle of a script. Sometimes you have to read some information from a file. The Bourne shell allows you to specify the source of information. Even though a script is connected to a pipe, you can ask the user for input. The C shell does not have this flexibility. It has a mechanism to get a line from standard input, but that is all it can do. You cannot have a C shell script get input from both a file and the terminal. With respect to file redirection, the Bourne shell. C shell is very limited. With the Bourne shell, you can send standard error. You can discard standard output, but keep the error. You can close any file descriptor, save current ones, and restore them. The C shell can't do any of these steps. If you want to make your script more robust, you must add. That is, your script must terminate. The C shell has limited abilities. You can either do nothing, ignore all signals, or trap all signals. It's an all or nothing situation. The Bourne shell can trap particular signals, and call a special routine. You can retain the process ID of a background process. This allows you to relay signals received to other processes under your control. The C shell cannot do this. You can use the C shell for simple scripts. If you don't add many new features, and only write scripts for yourself. C shell may be fine for you. But it is a time bomb. There are many times. I wanted to add a new feature to a C shell script. Or else I tried to port a C shell script to a different system. Yes, you can use the C shell. Use it for as long as you want. Tick.. Tick.. Tick.. This is my second tutorial on the C shell. This month, I will discuss. Like all shells, the C shell examines each line, and breaks it up into. The first word is a command, and additional words are. The command. more *uses a meta- character, the asterisk. The shell sees the asterisk, examines the current directory, and transforms. There are many other meta- characters. Some are very subtle. Consider this meta- character example. The meta- character? It's the space. In this case, the space indicates the end of one filename. The space, tab, and new- line- character are used by the C shell to. The Bourne shell allows more control, as any character can be. These meta- characters are an integral part of UNIX. Or rather, an integral part. A meta- character is simply a character with. The file system doesn't really care about meta- characters. You can have a filename that contains a space, or an asterisk, or any other. Similarly, you can specify any meta- character as an argument. Understanding which characters are meta- characters, what they. Most learn by trial and error. Trouble is, the C shell is trickier. One way to discover these characters is to use the. C shell will echo, and which. Here is the list of meta- characters, and a quick description of the. List of C Chell Meta- Characters |. Meta- character Meaning |. End of command |. End of word |. End of word |. History |. |# Comment |. Variable |. |& End of command arguments, launch in background |. Start sub- shell |. End sub- shell |. Start in- line expansion |. End in- line expansion |. End of command arguments, Pipe into next command |. Input Redirection |. Output Redirection |. Multi- character Filename expansion (a. Single- character Filename expansion (a. Character Set Filename expansion (a. Retrieving System Information via Command Line on Windows. In Windows operating systems there’s a command- line utility called Windows Management Instrumentation Command- Line (WMIC) which allows you to retrieve plenty of system and hardware information. In this article I’ll show you some exemplary commands. Basic Usage. To get a list of switches and aliases, type: wmic /? The /? switch can be appended to any command in order to get further information about the available options. Basically, to get system information, you just need to append an alias name to the wmic command, i. List Output. The output however is quite confusing, so you might wanna prefer the list option. Useful list formats are “full” and “brief”. Since the “brief” one comes out as a table, you can append the /format switch to get a list instead. You can copy the output directly into the clipboard by piping it into clip: wmic baseboard list brief /format: list | clip. Exporting Formatted Output. It’s also possible to export the output in formats like CSV or HTML. To get a list of available formats, type: wmic baseboard list /format /? Then you can export the output like this: wmic baseboard list /format: list > C: \output. C: \output. csvwmic memorychip list /format: hform > C: \output. Fix the “Invalid XSL format (or) file name” Error. If you use the /format switch you might encounter this error. This happens if your system’s locale setting differs from the language the operating system was originally installed in. Unfortunately the /locale switch does not seem to work so you have to manually fix the problem: In Windows Explorer go to: %WINDIR%\System. US (or your corresponding locale folder)Search for: *. You should find 5 files; select and copy these. Go to: %WINDIR%\System. Create a new folder for your locale (i. DE” for Germany)Go into the new folder and paste the files. Retrieve Only Chosen Attributes. To not get the full list of attributes but only a few, type: wmic baseboard get manufacturer,product,version /format: list. To find out the available attributes for an alias, type: wmic nic get /? Determine the Model Name of a Notebookwmic csproduct list full. Using the Powershell. With the wmic command it does not seem to be possible to get information about the video card. This however does work with the powershell and the following command: Get- Wmi. Object Win. 32_Videocontroller. Some classes don’t output everything by default. In this case do: Get- Wmi. Object Win. 32_Operating. System | Format- List *To show only chosen information: Get- Wmi. Object Win. 32_Videocontroller | Select- Object - Property Caption,Description,Name,Videoprocessor | Format- List *To get a list of all available classes, type: Get- Wmi. Object - List- Namespace"root\cimv. Sort. Some examples: Get- Wmi. Object Win. 32_Computer. System. Get- Wmi. Object Win. 32_Base. Board. Get- Wmi. Object Win. Bios. Get- Wmi. Object Win. Processor. Get- Wmi. Object Win. 32_Physical. Memory. Get- Wmi. Object Win. 32_Disk. Drive. Get- Wmi. Object Win. Logical. Disk. Get- Wmi. Object Win. 32_Network. Adapter. Get- Wmi. Object Win. 32_Operating. System. By changing the namespace (root\cimv. To get a list of available namespaces, type: Get- Wmi. Object - Class __Namespace - Namespace root | Format- Table name. To search for specific values, you can perform an SQL- like query: Get- Wmi. Object - Query"Select * From Win. Service Where State='Running'"| Format- Table Name,Description,Process. Id. Some classes provide methods that can be executed. To find out the available methods, enter the first command. To execute a method, append it to a Query: Get- Wmi. Object Win. 32_Service | Get- Member - Member. Type Method(Get- Wmi. Object - Query"Select * From Win. Service Where Name='wuauserv'"). Stop. Service()(Get- Wmi. Object - Query"Select * From Win. Service Where Name='wuauserv'"). Start. Service().
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