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TMPDIR

UNIX environment variable

Wikipedia contributorsAdapted for Fathomly · View authors
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Source updated March 30, 2026

TMPDIR is the canonical environment variable in Unix and POSIX that should be used to specify a temporary directory for scratch space. Most Unix programs will honor this setting and use its value to denote the scratch area for temporary files instead of the common default of /tmp or /var/tmp.

Other forms sometimes accepted are TEMP, TEMPDIR and TMP, but these alternatives are used more commonly by non-POSIX operating systems or non-conformant programs.

TMPDIR is specified in various Unix and similar standards, e.g. per the Single UNIX Specification.

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This article is adapted from the Wikipedia article “TMPDIR”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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