A lot of echo behavior that script writers rely on is in fact unspecified. A string to be written to standard output. If the first operand is -n, or if any of the operands contain a character, the results are implementation-defined. Thus whenever you want to write something to stdout and it's not for the purpose of printing a message to the user, the recommendation is to use printf as the behavior of printf is exactly defined. My function uses stdout to pass out a result, this is not a message for the user and thus only using printf guarantees perfect portability.
Note also that this only work in bash and compatible shells. I don't believe the substitutions work in the simple shell sh.
Hey guys I know it's an old thread but I am just posting this for reference to anybody else who visited this like me. It displays the absolute path of the file supplied, but only if it exists. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 11 years, 3 months ago. Active 11 months ago. Viewed k times. Here's a sample implementation, abspath. I would argue that DennisWilliamson's answer using -m option is superior for usually being more portable and working with files that don't exist.
Or Flimm's answer; both are good solutions. Bannier's however answers my original question best. OSX users: see this answer — Ian. Possible duplicate of Bash: retrieve absolute path given relative — user. Add a comment. Active Oldest Votes. Boris 9, 7 7 gold badges 72 72 silver badges 74 74 bronze badges.
Benjamin Bannier Benjamin Bannier But note that it is an external command not a shell built-in and may not be present in every system by default, i. In Debian it resides in a separate package with the same name. I added to my path a realpath consisting of: github. Dalin: Try installing coreutils. The binary is named grealpath. This tool was introduced in GNU coreutils 8. WalterTross, it is available from the coreutils formula via Homebrew. Show 16 more comments. Dennis Williamson Dennis Williamson k 87 87 gold badges silver badges bronze badges.
I would rather use '-f' instead of '-e' so that we can see absolute path of a nonexistent file. This looks like the simplest to me, while also being portable. It seems to me that -m is the best option to use.
Or did you mean those options are not found on OS X? It seems to be a stunted BSD version If the given argument is not a symbolic link, readlink will print nothing and exit with an error , so readlink won't work for this purpose on OSX — SnoringFrog.
Show 6 more comments. James Bedford Don't forget to quote all the stuff. If you don't understand why, try your program on a file a b two spaces between a and b, SO eats one of them. Show 8 more comments. Expanding on dogbane's answer above here it is expressed as a function:! Why do I like this solution? What if dir doesn't exist? You can expand the function to handle that situation:! How do you handle trailing '..
Well, it does give an absolute path in that case, but not a minimal one. If you want to resolve the '.. Not sure I understand your comment. What is it in the solution proposed here that excludes use from an interactive environment?
I would like to add that realpath comes from coreutils package, which also contains tools such as who , touch or cat. It's quite standar set of GNU tools, so you can be quite sure that this is installed on almost any linux based machine.
That said, you are right: there are 2 issues with it: i you will likely miss it in default install on non GNU unix systems like OpenBSD ii this tools was introduced in version 8. Well, it seems at least that Continuum Analytics makers of the Anaconda Python distribution liked this answer. It is implemented with a reference linking back here in their "activate" script , which is used to activate virtual environments created by the conda tool.
So… good one! This only works for directories since there is no else and cannot cope with ".. See my answer that should handle everything: stackoverflow. It may become somewhat standard over time, but it's certainly not now. Bash is more widely used than that. Flimm Flimm k 35 35 gold badges silver badges bronze badges. This instructs Python to ignore backslashes. An absolute, or full, path begins with a drive letter followed by a colon, such as D:.
A relative path refers to a location that is relative to a current directory. Relative paths make use of two special symbols, a dot. Double dots are used for moving up in the hierarchy. A single dot represents the current directory itself. The current directory is sometimes referred to as the root directory.
If you wanted to navigate to the Landuse directory from the current directory Soils , you could type the following in the Windows Explorer Address box:. When you create an ArcMap or ArcScene or ArcGlobe document, you can specify that paths will be stored as relative paths. To set this option, look under the File menu and click Map Document Properties. Here, you can specify whether to store absolute or relative paths.
For example, if your document is stored in. When you open Newmap. This conversion is always relative to the location of the map document the current directory.
Relative paths cannot span disk drives. That is, if the root directory is on drive D , you cannot use relative paths to navigate to a directory on drive E. When you store your map document using relative paths, only those paths that are on the same drive are converted and stored. Learn more about referencing data in a map document.
Just like data in ArcMap, you can specify that paths in your model tools will be stored as relative paths. The current directory used for relative paths is the directory where the tool's toolbox resides. The relative path option converts and stores paths to the following:. To proceed, choose your topic of interest from the following list. In the example above, the absolute path contains the full path to the file and not only the file name as seen in the non absolute path.
In this example, if you were in a directory that did not contain "calc. However, when using an absolute path you can be in any directory and the computer would know where to open the "calc.
You can determine the absolute path of any file in Windows by right-clicking a file and then clicking Properties. In the file properties first look at the "Location:" which is the path to the file.
Next, add a backslash and then the file name to the end of the path. From the Windows command line , you can find the absolute path of any file by looking at the current directory. In other words, the absolute path is the full directory path plus the file name. In the example above, the absolute path contains the full path to the cgi-bin directory on that computer. The relative path begins with a dot period , representing the current directory also called the "working directory".
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