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website/docs/language/functions/fileset.mdx

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+---
+page_title: fileset - Functions - Configuration Language
+description: The fileset function enumerates a set of regular file names given a pattern.
+---
+
+# `fileset` Function
+
+`fileset` enumerates a set of regular file names given a path and pattern.
+The path is automatically removed from the resulting set of file names and any
+result still containing path separators always returns forward slash (`/`) as
+the path separator for cross-system compatibility.
+
+```hcl
+fileset(path, pattern)
+```
+
+Supported pattern matches:
+
+- `*` - matches any sequence of non-separator characters
+- `**` - matches any sequence of characters, including separator characters
+- `?` - matches any single non-separator character
+- `{alternative1,...}` - matches a sequence of characters if one of the comma-separated alternatives matches
+- `[CLASS]` - matches any single non-separator character inside a class of characters (see below)
+- `[^CLASS]` - matches any single non-separator character outside a class of characters (see below)
+
+Note that the doublestar (`**`) must appear as a path component by itself. A
+pattern such as /path\*\* is invalid and will be treated the same as /path\*, but
+/path\*/\*\* should achieve the desired result.
+
+Character classes support the following:
+
+- `[abc]` - matches any single character within the set
+- `[a-z]` - matches any single character within the range
+
+Functions are evaluated during configuration parsing rather than at apply time,
+so this function can only be used with files that are already present on disk
+before Terraform takes any actions.
+
+## Examples
+
+```
+> fileset(path.module, "files/*.txt")
+[
+  "files/hello.txt",
+  "files/world.txt",
+]
+
+> fileset(path.module, "files/{hello,world}.txt")
+[
+  "files/hello.txt",
+  "files/world.txt",
+]
+
+> fileset("${path.module}/files", "*")
+[
+  "hello.txt",
+  "world.txt",
+]
+
+> fileset("${path.module}/files", "**")
+[
+  "hello.txt",
+  "world.txt",
+  "subdirectory/anotherfile.txt",
+]
+```
+
+A common use of `fileset` is to create one resource instance per matched file, using
+[the `for_each` meta-argument](/language/meta-arguments/for_each):
+
+```hcl
+resource "example_thing" "example" {
+  for_each = fileset(path.module, "files/*")
+
+  # other configuration using each.value
+}
+```