---
name: "ohexbuf"
section: "3bobcat"
platform: "linux"
package: "libbobcat-dev"
version: "6.07.01-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/ohexbuf"
---

# ohexbuf(3bobcat)

Writes characters written to an ostream as hex values

## NAME

FBB::OHexBuf - Writes characters written to an ostream as hex values

## SYNOPSIS

**#include \<bobcat/ohexbuf\>**\
 Linking option: *-lbobcat*

## DESCRIPTION

**OHexBuf** is a specialization of *FBB::OFilterBuf* inserting all the characters it receives to a destination file as 2-character wide hexadecimal values. Optionally a maximum linelength can be specified.

Note that all information received by an *OHexBuf* object is inserted as (a series of) hexadecimal values, not only plain characters. E.g., when inserting the value 123 the characters *’1’, ’2’* and *’3’* are successively inserted and so this will result in the string *313233* being inserted into the destination stream.

## NAMESPACE

**FBB**\
 All constructors, members, operators and manipulators, mentioned in this man-page, are defined in the namespace **FBB**.

## INHERITS FROM

*FBB::OFilterBuf*

## CONSTRUCTOR

- o

  **OHexBuf(std::ostream &stream, size\_t width = 0, std::string** **const &separator = "")**:\
   The hexadecimal characters produced by the *OFilterBuf* object are inserted into *stream*. Optionally the maximum line width (in number of characters) may be specified using *width*. The (default) value 0 indicates that no line breaks are requested. The parameter *separator* defines the separator that’s inserted between hexadecimal character values. By default no separator is used.

Copy and move constructors (and assignment operators) are not available.

The destructor writes any buffered information to the destination stream and then flushes the destination stream. Finally, the destructor restores the original formatting flags of the receiving *ostream*.

## MEMBER FUNCTIONS

All members of **FBB::OFilterBuf**, in particular its *out()* and *reset* members are available, as **FBB::OHexBuf** inherits from this class.

- o

  **void eoi()**:\
   This member completes the current hexadecimal character conversion, clears the separator, and no longer uses a the maximum output line width. Instead of calling this member the *eoi* manipulator (see below) can be used.

-

  - o

  **void separator(bool reset = true)**:\
   This member clears the separator that’s inserted between hexadecimal character values. When the *reset* parameter is set to *true* (which is the default) the currently used output width is reset to 0.

-

  - o

  **void separator(std::string const &separator, bool reset = true)**:\
   This member resets the separator that’s inserted between hexadecimal character values to *separator’s* value. When the *reset* parameter is set to *true* (which is the default) the currently used output width is reset to 0.

-

  - o

  **void setWidth(size\_t width)**:\
   This member sets the width of the generated output lines to *width* characters. No maximum line width is used when *width = 0*  is specified.

-

  - o

  **size\_t size() const**:\
   This member returns the next column offset where the next hexadecimal character will appear. If a maximum line length is requested and *size()* does not return 0 then the last line inserted was not terminated by a *’\\n’* character. See also the example below.

-

  This member’s return value is undefined if  no maximum line length was requested.

## MANIPULATOR

- o

  **FBB::eoi**:\
   The *eoi* manipulator can be inserted into the *ostream* to complete the hexaecimal conversion. It acts identically to calling the *end* member. If inserted into a plain *std::ostream* nothing happens.

## STATIC MEMBER

- o

  **std::string text2bin(std::string const &in)**:\
   This static member converts a series of hexadecimal characters generated by a *OHexBuf* object back to their binary form. E.g, when called as *OHexBuf::text2bin("736d616c6c206976")* then the returned *std::string* will contain 8 characters, having respectively the binary values 0x73, 0x6d, 0x61, 0x6c, 0x6c, 0x20, 0x69, and 0x76.

-

  This function does *not* verify whether its argument is properly formed. A properly formed argument consists of an even number of hexadecimal number characters (’0’ until ’9’, ’a’ until ’f’ (or uppercase)). For improperly formed arguments the return value is undefined.

-

  ## EXAMPLE

```
    #include <iostream>
    #include <bobcat/ohexbuf>
    using namespace std;
    using namespace FBB;
    int main()
    {
        OHexBuf ohex(cout, 40);
        ostream out(&ohex);
        out << cin.rdbuf();
        if (ohex.size())
            cout << ’\n’;
    }
```

## FILES

*bobcat/ohexbuf* - defines the class interface

## SEE ALSO

[**bobcat**(7)](/bobcat/7.md), [**ofilterbuf**(3bobcat)](/ofilterbuf/3bobcat.md)

## BUGS

None Reported.

## BOBCAT PROJECT FILES

- o

  *https://fbb-git.gitlab.io/bobcat/*: gitlab project page;

Debian Bobcat project files:

- o

  *libbobcat6*: debian package containing the shared library, changelog and copyright note;

- o

  *libbobcat-dev*: debian package containing the static library, headers, manual pages, and developer info;

## BOBCAT

Bobcat is an acronym of \`Brokken’s Own Base Classes And Templates’.

## COPYRIGHT

This is free software, distributed under the terms of the GNU General Public License (GPL).

## AUTHOR

Frank B. Brokken (**f.b.brokken@rug.nl**).