---
name: "h2ph"
section: "1"
platform: "linux"
package: "perl"
version: "5.40.1-6+deb13u1"
release: "Debian 13 (Trixie)"
platforms: ["linux", "openbsd"]
url: "https://new.carta.tech/h2ph"
---

# h2ph(1)

convert .h C header files to .ph Perl header files

## NAME

h2ph - convert .h C header files to .ph Perl header files

## SYNOPSIS

**h2ph \[-d destination directory\] \[-r \| -a\] \[-l\] \[-h\] \[-e\] \[-D\] \[-Q\]** **\[headerfiles\]**

## DESCRIPTION

*h2ph* converts any C header files specified to the corresponding Perl header file format. It is most easily run while in /usr/include:

```
        cd /usr/include; h2ph * sys/*
```

or

```
        cd /usr/include; h2ph * sys/* arpa/* netinet/*
```

or

```
        cd /usr/include; h2ph -r -l .
```

The output files are placed in the hierarchy rooted at Perl's architecture dependent library directory.  You can specify a different hierarchy with a **-d** switch.

If run with no arguments, filters standard input to standard output.

## OPTIONS

- \-d destination\_dir

  Put the resulting **.ph** files beneath **destination\_dir**, instead of beneath the default Perl library location (`$Config{'installsitearch'}`).

- \-r

  Run recursively; if any of **headerfiles** are directories, then run *h2ph* on all files in those directories (and their subdirectories, etc.).  **-r** and **-a** are mutually exclusive.

- \-a

  Run automagically; convert **headerfiles**, as well as any **.h** files which they include.  This option will search for **.h** files in all directories which your C compiler ordinarily uses.  **-a** and **-r** are mutually exclusive.

- \-l

  Symbolic links will be replicated in the destination directory.  If **-l** is not specified, then links are skipped over.

- \-h

  Put 'hints' in the .ph files which will help in locating problems with *h2ph*.  In those cases when you **require** a **.ph** file containing syntax errors, instead of the cryptic

  ```
          [ some error condition ] at (eval mmm) line nnn
  ```

  you will see the slightly more helpful

  ```
          [ some error condition ] at filename.ph line nnn
  ```

  However, the **.ph** files almost double in size when built using **-h**.

- \-e

  If an error is encountered during conversion, output file will be removed and a warning emitted instead of terminating the conversion immediately.

- \-D

  Include the code from the **.h** file as a comment in the **.ph** file. This is primarily used for debugging *h2ph*.

- \-Q

  'Quiet' mode; don't print out the names of the files being converted.

## ENVIRONMENT

No environment variables are used.

## FILES

```
 /usr/include/*.h
 /usr/include/sys/*.h
```

etc.

## AUTHOR

Larry Wall

## SEE ALSO

[**perl**(1)](/perl/1.md)

## DIAGNOSTICS

The usual warnings if it can't read or write the files involved.

## BUGS

Doesn't construct the `%sizeof` array for you.

It doesn't handle all C constructs, but it does attempt to isolate definitions inside evals so that you can get at the definitions that it can translate.

It's only intended as a rough tool. You may need to dicker with the files produced.

You have to run this program by hand; it's not run as part of the Perl installation.

Doesn't handle complicated expressions built piecemeal, a la:

```
    enum {
        FIRST_VALUE,
        SECOND_VALUE,
    #ifdef ABC
        THIRD_VALUE
    #endif
    };
```

Doesn't necessarily locate all of your C compiler's internally-defined symbols.