Where is the temporary directory in Linux?

Question

Does Linux have a standard temporary directory for general use, like Windows's C:\Temp folder? If so, where is it located? I found an SO question about finding a tmp directory programmatically, but I want to set a temp location in an XML config file ahead of time.

Answer 1

The Filesystem Hierarchy Standard says:

The /tmp directory must be made available for programs that require temporary files.

Programs must not assume that any files or directories in /tmp are preserved between invocations of the program.

and

The /var/tmp directory is made available for programs that require temporary files or directories that are preserved between system reboots. Therefore, data stored in /var/tmp is more persistent than data in /tmp.

Files and directories located in /var/tmp must not be deleted when the system is booted. Although data stored in /var/tmp is typically deleted in a site-specific manner, it is recommended that deletions occur at a less frequent interval than /tmp.

Answer 2

Yes /tmp is for general use. See here and here On the Filesystem Hierarchy Standard.

/tmp/ Temporary files (see also /var/tmp). Often not preserved between system reboots.

With some more details listed in the PDF.

Answer 3

You cannot choose a single temporary directory name ahead of time that will work for any Linux system. In fact, you can't do that on Windows either. According to Wikipedia's article on temporary folders, the temporary directory on Windows is determined by the environment variable TEMP. If you were simply using c:\Temp as a temporary directory on a Windows system that set TEMP to something else, then any program using your XML file to choose a temporary directory would fail.

In short, the system temporary directory is determined by the environment on all modern operating systems that I know of, including both Windows and any UNIX-like system. Setting a single static path as your temporary directory will only work as long as the defaults have not been changed.

Anyway, the standard temporary directory in a typical Linux system is /tmp. It is the equivalent of C:\Temp in the sense that it is only the default temporary directory, not universal. Even if /tmp is available, if a user (or the system) has set the TEMP environment variable, the value of that variable should be used instead.

You could try choosing a temporary directory relative to the user's home directory, which you can create.