PStreams
Public Types | Public Member Functions | Static Public Attributes | Protected Types | Private Types | Private Member Functions | Private Attributes | Static Private Attributes | List of all members
redi::basic_rpstream< CharT, Traits > Class Template Reference

Class template for Restricted PStreams. More...

#include <pstream.h>

Inheritance diagram for redi::basic_rpstream< CharT, Traits >:
redi::pstream_common< CharT, Traits > redi::pstreams

Public Types

typedef pbase_type::pmode pmode
 Type used to specify how to connect to the process.
 
typedef pbase_type::argv_type argv_type
 Type used to hold the arguments for a command.
 
typedef int fd_type
 Type used for file descriptors.
 

Public Member Functions

 basic_rpstream ()
 Default constructor, creates an uninitialised stream.
 
 basic_rpstream (const std::string &cmd, pmode mode=pstdout|pstdin)
 Constructor that initialises the stream by starting a process. More...
 
 basic_rpstream (const std::string &file, const argv_type &argv, pmode mode=pstdout|pstdin)
 Constructor that initialises the stream by starting a process. More...
 
 basic_rpstream (const argv_type &argv, pmode mode=pstdout|pstdin)
 Constructor that initialises the stream by starting a process. More...
 
 ~basic_rpstream ()
 Destructor.
 
void open (const std::string &cmd, pmode mode=pstdout|pstdin)
 Start a process. More...
 
void open (const std::string &file, const argv_type &argv, pmode mode=pstdout|pstdin)
 Start a process. More...
 
istream_type & out ()
 Obtain a reference to the istream that reads the process' stdout. More...
 
istream_type & err ()
 Obtain a reference to the istream that reads the process' stderr. More...
 

Static Public Attributes

static const pmode pstdin = std::ios_base::out
 Write to stdin.
 
static const pmode pstdout = std::ios_base::in
 Read from stdout.
 
static const pmode pstderr = std::ios_base::app
 Read from stderr.
 
static const pmode newpg = std::ios_base::trunc
 Create a new process group for the child process.
 

Protected Types

enum  { bufsz = 32 }
 
enum  { pbsz = 2 }
 

Private Types

typedef basic_pstreambuf< CharT, Traits > streambuf_type
 
enum  { bufsz = 32 }
 
enum  { pbsz = 2 }
 
typedef int fd_type
 Type used for file descriptors.
 

Private Member Functions

void do_open (const std::string &cmd, pmode mode)
 Start a process. More...
 
void do_open (const std::string &file, const argv_type &argv, pmode mode)
 Start a process. More...
 
void close ()
 Close the pipe. More...
 
bool is_open () const
 Report whether the stream's buffer has been initialised. More...
 
const std::string & command () const
 Return the command used to initialise the stream. More...
 
streambuf_typerdbuf () const
 Return a pointer to the stream buffer. More...
 

Private Attributes

std::string command_
 The command used to start the process.
 
streambuf_type buf_
 The stream buffer.
 

Static Private Attributes

static const pmode pstdin = std::ios_base::out
 Write to stdin.
 
static const pmode pstdout = std::ios_base::in
 Read from stdout.
 
static const pmode pstderr = std::ios_base::app
 Read from stderr.
 
static const pmode newpg = std::ios_base::trunc
 Create a new process group for the child process.
 

Detailed Description

template<typename CharT, typename Traits = std::char_traits<CharT>>
class redi::basic_rpstream< CharT, Traits >

Class template for Restricted PStreams.

Writing to an rpstream opened with pmode pstdin writes to the standard input of the command. It is not possible to read directly from an rpstream object, to use an rpstream as in istream you must call either basic_rpstream::out() or basic_rpstream::err(). This is to prevent accidental reads from the wrong input source. If the rpstream was not opened with pmode pstderr then the class cannot read the process' stderr, and basic_rpstream::err() will return an istream that reads from the process' stdout, and vice versa. Reading from an rpstream opened with pmode pstdout and/or pstderr reads the command's standard output and/or standard error. Any of the process' stdin, stdout or stderr that is not connected to the pstream (as specified by the pmode) will be the same as the process that created the pstream object, unless altered by the command itself.

Constructor & Destructor Documentation

template<typename CharT , typename Traits = std::char_traits<CharT>>
redi::basic_rpstream< CharT, Traits >::basic_rpstream ( const std::string &  cmd,
pmode  mode = pstdout|pstdin 
)
inlineexplicit

Constructor that initialises the stream by starting a process.

Initialises the stream buffer by calling do_open() with the supplied arguments.

Parameters
cmda string containing a shell command.
modethe I/O mode to use when opening the pipe.
See also
do_open(const std::string&, pmode)
template<typename CharT , typename Traits = std::char_traits<CharT>>
redi::basic_rpstream< CharT, Traits >::basic_rpstream ( const std::string &  file,
const argv_type argv,
pmode  mode = pstdout|pstdin 
)
inline

Constructor that initialises the stream by starting a process.

Initialises the stream buffer by calling do_open() with the supplied arguments.

Parameters
filea string containing the pathname of a program to execute.
argva vector of argument strings passed to the new program.
modethe I/O mode to use when opening the pipe.
See also
do_open(const std::string&, const argv_type&, pmode)
template<typename CharT , typename Traits = std::char_traits<CharT>>
redi::basic_rpstream< CharT, Traits >::basic_rpstream ( const argv_type argv,
pmode  mode = pstdout|pstdin 
)
inlineexplicit

Constructor that initialises the stream by starting a process.

Initialises the stream buffer by calling do_open(argv[0],argv,mode)

Parameters
argva vector of argument strings passed to the new program.
modethe I/O mode to use when opening the pipe.
See also
do_open(const std::string&, const argv_type&, pmode)

References redi::pstreams::pstdin, and redi::pstreams::pstdout.

Member Function Documentation

template<typename CharT , typename Traits = std::char_traits<CharT>>
istream_type& redi::basic_rpstream< CharT, Traits >::err ( )
inline

Obtain a reference to the istream that reads the process' stderr.

Returns
*this
template<typename CharT , typename Traits = std::char_traits<CharT>>
void redi::basic_rpstream< CharT, Traits >::open ( const std::string &  cmd,
pmode  mode = pstdout|pstdin 
)
inline

Start a process.

Calls do_open( cmd , mode ).

Parameters
cmda string containing a shell command.
modethe I/O mode to use when opening the pipe.
See also
do_open(const std::string&, pmode)
template<typename CharT , typename Traits = std::char_traits<CharT>>
void redi::basic_rpstream< CharT, Traits >::open ( const std::string &  file,
const argv_type argv,
pmode  mode = pstdout|pstdin 
)
inline

Start a process.

Calls do_open( file , argv , mode ).

Parameters
filea string containing the pathname of a program to execute.
argva vector of argument strings passed to the new program.
modethe I/O mode to use when opening the pipe.
See also
do_open(const std::string&, const argv_type&, pmode)
template<typename CharT , typename Traits = std::char_traits<CharT>>
istream_type& redi::basic_rpstream< CharT, Traits >::out ( )
inline

Obtain a reference to the istream that reads the process' stdout.

Returns
*this

The documentation for this class was generated from the following file: