PStreams
redi::basic_opstream< CharT, Traits > Class Template Reference

Class template for Output PStreams. More...

#include <pstream.h>

Inheritance diagram for redi::basic_opstream< CharT, Traits >:
redi::pstream_common< CharT, Traits > redi::pstreams 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_opstream ()
 Default constructor, creates an uninitialised stream.
 basic_opstream (const std::string &cmd, pmode mode=pstdin)
 Constructor that initialises the stream by starting a process.
 basic_opstream (const std::string &file, const argv_type &argv, pmode mode=pstdin)
 Constructor that initialises the stream by starting a process.
 basic_opstream (const argv_type &argv, pmode mode=pstdin)
 Constructor that initialises the stream by starting a process.
 ~basic_opstream ()
 Destructor.
void open (const std::string &cmd, pmode mode=pstdin)
 Start a process.
void open (const std::string &file, const argv_type &argv, pmode mode=pstdin)
 Start a process.
int close ()
bool is_open () const
 Report whether the stream's buffer has been initialised.
const std::string & command () const
 Return the command used to initialise the stream.
streambuf_typerdbuf () const
 Return a pointer to the stream buffer.

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

typedef basic_pstreambuf< CharT, Traits > streambuf_type
typedef std::basic_ios< CharT, Traits > ios_type
enum  { bufsz = 32 , pbsz = 2 }

Protected Member Functions

void do_open (const std::string &cmd, pmode mode)
 Start a process.
void do_open (const std::string &file, const argv_type &argv, pmode mode)
 Start a process.

Protected Attributes

std::string command_
 The command used to start the process.

(Note that these are not member symbols.)

template<typename C, typename T>
std::basic_ostream< C, T > & peof (std::basic_ostream< C, T > &s)
 Manipulator to close the pipe connected to the process' stdin.

Detailed Description

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

Class template for Output PStreams.

Writing to an open opstream writes to the standard input of the command; the command's standard output is the same as that of the process that created the pstream object, unless altered by the command itself.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum
protectedinherited
Enumerator
bufsz 

Size of pstreambuf buffers.

pbsz 

Number of putback characters kept.

Constructor & Destructor Documentation

◆ basic_opstream() [1/3]

template<typename CharT, typename Traits = std::char_traits<CharT>>
redi::basic_opstream< CharT, Traits >::basic_opstream ( const std::string & cmd,
pmode mode = 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)

◆ basic_opstream() [2/3]

template<typename CharT, typename Traits = std::char_traits<CharT>>
redi::basic_opstream< CharT, Traits >::basic_opstream ( const std::string & file,
const argv_type & argv,
pmode mode = 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)

◆ basic_opstream() [3/3]

template<typename CharT, typename Traits = std::char_traits<CharT>>
redi::basic_opstream< CharT, Traits >::basic_opstream ( const argv_type & argv,
pmode mode = pstdin )
inlineexplicit

Constructor that initialises the stream by starting a process.

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

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)

◆ ~basic_opstream()

template<typename CharT, typename Traits = std::char_traits<CharT>>
redi::basic_opstream< CharT, Traits >::~basic_opstream ( )
inline

Destructor.

Closes the stream and waits for the child to exit.

Member Function Documentation

◆ close()

template<typename C, typename T>
int redi::pstream_common< C, T >::close ( )
inlineinherited

Close the pipe, returning the program's exit status, as pclose(3) does.

Calls rdbuf->close() and sets failbit on error. Returns process's exit status, as pclose(3) does.

References buf_.

◆ command()

template<typename C, typename T>
const std::string & redi::pstream_common< C, T >::command ( ) const
inlineinherited

Return the command used to initialise the stream.

Returns
a string containing the command used to initialise the stream.

References command_.

◆ do_open() [1/2]

template<typename C, typename T>
void redi::pstream_common< C, T >::do_open ( const std::string & cmd,
pmode mode )
inlineprotectedinherited

◆ do_open() [2/2]

template<typename C, typename T>
void redi::pstream_common< C, T >::do_open ( const std::string & file,
const argv_type & argv,
pmode mode )
inlineprotectedinherited

Start a process.

Calls rdbuf()->open( file, argv, mode ) and sets failbit on error.

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
basic_pstreambuf::open(const std::string&, const argv_type&, pmode)

References buf_, and command_.

◆ is_open()

template<typename C, typename T>
bool redi::pstream_common< C, T >::is_open ( ) const
inlineinherited

Report whether the stream's buffer has been initialised.

Returns
rdbuf()->is_open().
See also
basic_pstreambuf::is_open()

References buf_.

◆ open() [1/2]

template<typename CharT, typename Traits = std::char_traits<CharT>>
void redi::basic_opstream< CharT, Traits >::open ( const std::string & cmd,
pmode mode = pstdin )
inline

Start a process.

Calls do_open( cmd , mode|pstdin ).

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)

◆ open() [2/2]

template<typename CharT, typename Traits = std::char_traits<CharT>>
void redi::basic_opstream< CharT, Traits >::open ( const std::string & file,
const argv_type & argv,
pmode mode = pstdin )
inline

Start a process.

Calls do_open( file , argv , mode|pstdin ).

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)

◆ rdbuf()

template<typename C, typename T>
pstream_common< C, T >::streambuf_type * redi::pstream_common< C, T >::rdbuf ( ) const
inlineinherited

Return a pointer to the stream buffer.

Returns
a pointer to the private stream buffer member.

References buf_.

◆ peof()

template<typename C, typename T>
std::basic_ostream< C, T > & peof ( std::basic_ostream< C, T > & s)
related

Manipulator to close the pipe connected to the process' stdin.

When inserted into an output pstream the manipulator calls basic_pstreambuf<C,T>::peof() to close the output pipe, causing the child process to receive the end-of-file indicator on subsequent reads from its stdin stream.

Parameters
sAn output PStream class.
Returns
The stream object the manipulator was invoked on.
See also
basic_pstreambuf<C,T>::peof() basic_pstream basic_rpstream

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