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

# syslogstream(3bobcat)

An output stream inserting syslog messages

## NAME

FBB::SyslogStream - An output stream inserting syslog messages

## SYNOPSIS

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

## DESCRIPTION

**FBB::SyslogStream** objects may be used as a *std::ostream* to write syslog messages using stream facilities.

Multiple separate insertions can be used to create a single syslog message: the message is only sent to the syslog daemon after receiving a *flush* command (e.g., after inserting *std::flush* or *std::endl*). Non-printable characters (like *’\\n’*) show up in the syslog message as octal values, preceded by *#* (e.g., *#012* for *’\\n’*). The newline normally inserted by *std::endl* is ignored: **SyslogStream** objects interpret *std::endl* like *std::flush*.

One series of insertions may contain multiple *std::endl* or *std::flush* manipulators. At each of these manipulators a new message is sent to the syslog daemon, containing all info that has so far been buffered. After sending a message to the syslog daemon, the **SyslogStream**’s internal buffer is cleared.

## NAMESPACE

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

## INHERITS FROM

**std::ostream**

## ENUMERATIONS

The following enumerations are defined in the namespace **FBB**:

**Priority**:

The values of this enumeration match the corresponding priority *LOG\_xxx* values used with [**syslog**(3)](/syslog/3.md):

- o

  **EMERG**:\
   system is unusable;

- o

  **ALERT**:\
   action must be taken immediately;

- o

  **CRIT**:\
   critical conditions;

- o

  **ERR**:\
   error conditions;

- o

  **WARNING**:\
   warning conditions;

- o

  **NOTICE**:\
   normal, but significant, condition;

- o

  **INFO**:\
   informational message;

- o

  **DEBUG**:\
   debug-level message; The *setMask* member (see below) can be used to select which type of messages will actually be processed by the syslog daemon.

**PriorityType**:

This enumeration has two values fine-tuning the type of messages that are actually processed by the syslog daemon:

- o

  **SINGLE**:\
   Only messages of the priority specified at the *setMask* call are processed by the syslog daemon;

- o

  **UPTO**:\
   Messages of priority *EMERG* up to the the priority specified at the *setMask* call are processed by the syslog daemon; By default, the syslog daemon processes all messages it receives.

**Facility**:

The values of this enumeration match the corresponding facility *LOG\_xxx* values used with [**syslog**(3)](/syslog/3.md):

- o

  **AUTHPRIV**:\
   security/authorization messages (private)

- o

  **CRON**:\
   clock daemon (*cron* and *at*)

- o

  **DAEMON**:\
   other system daemons

- o

  **KERN**:\
   kernel messages

- o

  **LOCAL0**:\
   reserved for local use. **LOCAL1** through **LOCAL7** are available as well.

- o

  **LPR**:\
   line printer subsystem

- o

  **MAIL**:\
   mail subsystem

- o

  **NEWS**:\
   *USENET* news subsystem

- o

  **SYSLOGBUF**:\
   messages generated internally by *syslogbufd*

- o

  **USER**:\
   generic user-level messages

- o

  **UUCP**:\
   UUCP subsystem

## CONSTRUCTORS

- o

  **SyslogStream(string const &ident = "",** **FBB::Priority priority = FBB::NOTICE,** **FBB::Facility facility = FBB::USER,** **int option = 0)**:\
   This constructor initializes a **SyslogStream** object.  The *ident* parameter is usually the name of the program. Its content are prepended to syslog messages.

-

  The *priority* parameter determines the default importance of the message sent to the syslog daemon. By default messages are sent to the syslog daemon with priority **FBB::NOTICE**. Syslog messages may be given different priority by inserting a **SyslogStream** manipulator (see below). The priority set at construction time may also be modified using the *setPriority* and *setDefaultPriority* members.

-

  Which messages actually appear in log facilities is not determined by the messages’ priorities, but by syslog’s *log mask*. The log mask can be set by the static member *setMask* (see below).

-

  The *facility* parameter determines the type of program doing the logging. By default **FBB::USER** is used.

-

  The *option* parameter may be used to specify various options (use the binary \`*bitor*’ (\`*\|*’) operator to combine options):

-

  **LOG\_CONS**: write directly to system console  if  there  is  an error while sending to system logger \
   **LOG\_NDELAY**: open the connection immediately (normally, the con- nection is opened when the first message is logged) \
   **LOG\_PERROR**: print to stderr as well \
   **LOG\_\_PID**: include PID with each message \

-

  By default no options are used.

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

## MEMBER FUNCTIONS

All members of **std::ostream** are available, as **FBB::SyslogStream** inherits from this class.

- o

  **void close()**:\
   If the **SyslogStream**’s internal buffer is not empty it is flushed to the syslog daemon. Thereafer [**closelog**(3)](/closelog/3.md) is called.

- o

  **Priority defaultPriority() const**:\
   Returns the current default priority. I.e., the priority that will be used for the messages after inserting *endl* or *flush*.

- o

  **void open(string const &ident,** **FBB::Priority priority = FBB::NOTICE,** **FBB::Facility facility = FBB::USER,** **int option = 0)**:\
   Redefines the current identifier, priority, facility and options that are used when sending messages to the syslog daemon. If the **SyslogStream**’s internal buffer is not empty it is first flushed to the syslog daemon using the identifier, priority and options that were active just before calling *open*.

- o

  **Priority priority() const**:\
   Returns the next priority. I.e., the priority that will be used for the next message that is sent to the syslog daemon.

- o

  **Priority setDefaultPriority(Priority priority)**:\
   Changes the default priority of the next message that is sent to the syslog daemon after inserting *std::eoln* or *std::flush*. The previously active default priority is returned.

- o

  **Priority setPriority(Priority priority)**:\
   Changes the priority for the next message that is sent to the syslog daemon after inserting *std::eoln* or *std::flush*. Subsequent messages will again use the default priority. The previously active priority setting is returned.

## STATIC MEMBER FUNCTIONS

- o

  **Priority setMask(Priority priority, PriorityMask upTo)**:\
   Syslog messages of (if *upTo* equals *SINGLE*) or up to (if *upTo* equals *UPTO*) the indicated priority are processed by the syslog daemon.

- o

  **Priority setMask(Priority priority, Priority ...priorities)**:\
   Syslog messages of the priorities passed to *setMask* are processed by the syslog daemon. At least one priority must be specified.

- o

  **Facility stoF(std::string const &name, Facility facility = USER)**:\
   Returns the facility matching the name of the facility provided by *name*. Facility matching is performed case insensitively. E.g., if *name* contains *daemon*, facility *FBB::DAEMON* is returned. If *name* does not match any facility name then the value of this function’s second argument is returned. The function’s name (*stoF*) was used in analogy of the various *sto...* conversion functions that were made available by the **C++11** standard.

- o

  **Priority stoP(std::string const &name, Priority priority = NOTICE)**:\
   Returns the priority matching the name of the priority provided by *name*. Priority matching is performed case insensitively. E.g., if *name* contains *emerg*, priority *FBB::EMERG* is returned. If *name* does not match any priority name then the value of this function’s second argument is returned. The function’s name (*stoP*) was used in analogy of the various *sto...* conversion functions that were made available by the **C++11** standard.

## MANIPULATORS

The following set of manipulators are all defined as (static) members. They may be inserted into an **FBB::SyslogStream** object. Except for the last manipulator (*strerrno*), they have the following characteristics in common:

- o

  They change the priority of the messages that are subsequently inserted by the **FBB::SyslogStream** object, thus acting like a separate *setPriority* call.

- o

  When inserting multiple manipulators before the inserted message is flushed (e.g., using the *std::flush* or the *std::endl* manipulators) the last inserted **FBB::SyslogStream** manipulator will be used.

- o

  If the manipulators are not inserted into an **FBB::SyslogStream** object (but in another *std::ostream* type of object) then they perform no action.

Here are the available manipulators:

- o

  **SyslogStream::alert**:\
   Messages are inserted with priority **FBB::ALERT**.

- o

  **SyslogStream::crit**:\
   Message are inserted with priority **FBB::CRIT**.

- o

  **SyslogStream::debug**:\
   Messages are inserted with priority **FBB::DEBUG**.

- o

  **SyslogStream::emerg**:\
   Messages are inserted with priority **FBB::EMERG**.

- o

  **SyslogStream::err**:\
   Messages are inserted with priority **FBB::ERR**.

- o

  **SyslogStream::info**:\
   Messages are inserted with priority **FBB::INFO**.

- o

  **SyslogStream::notice**:\
   Messages are inserted with priority **FBB::NOTICE**.

- o

  **SyslogStream::strerrno**:\
   This manipulator inserts the textual interpretation of *std::errno*’s current value into a *std::ostream*. Note that, different from the other manipulators, the object into which this manipulator is inserted does not have to be a **FBB::SyslogStream** object.

- o

  **SyslogStream::warning**:\
   Messages are inserted with priority **FBB::WARNING**.

## EXAMPLE

```
#include <bobcat/syslogstream>
using namespace std;
using namespace FBB;
int main(int argc, char **argv)
{
    SyslogStream sls(argv[0]);
    sls << SyslogStream::debug << "Hello world" << flush <<
           SyslogStream::strerrno << endl;
}
```

## FILES

*bobcat/syslogstream* - defines the class interface

## SEE ALSO

[**bobcat**(7)](/bobcat/7.md), [**closelog**(3)](/closelog/3.md), [**log**(3bobcat)](/log/3bobcat.md), [**openlog**(3)](/openlog/3.md),  [**rsyslogd**(8)](/rsyslogd/8.md), [**syslog**(3)](/syslog/3.md), [**syslogbuf**(3bobcat)](/syslogbuf/3bobcat.md)

## BUGS

The constructor’s *option* parameter is an *int*. Because of this, *int* values rather than enumeration values are passed to the constructor. It is the responsibility of the programmer to pass defined option values only.

## 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**).