JSYSTEM::JProcess Class Reference

Streaming of input and output from Linux command. More...

#include <JProcess.hh>

Inheritance diagram for JSYSTEM::JProcess:

Public Member Functions
	JProcess ()
	Default constructor. More...
	JProcess (const std::string &command)
	Constructor. More...
	~JProcess ()
	Destructor. More...
JFileInputStreamBuffer *	getInputStreamBuffer (const std::size_t size=65536)
	Get pointer to input stream buffer connected to the normal output stream. More...
JFileInputStreamBuffer *	getErrorStreamBuffer (const std::size_t size=65536)
	Get pointer to input stream buffer connected to the error output stream. More...
JFileOutputStreamBuffer *	getOutputStreamBuffer (const std::size_t size=65536)
	Get pointer to output stream buffer connected to the normal input stream. More...

Protected Member Functions
void	execute (const char *path, const char *arg0, const char *arg1=(char *) NULL, const char *arg2=(char *) NULL, const char *arg3=(char *) NULL, const char *arg4=(char *) NULL, const char *arg5=(char *) NULL, const char *arg6=(char *) NULL, const char *arg7=(char *) NULL, const char *arg8=(char *) NULL, const char *arg9=(char *) NULL)
	Execute command. More...

Protected Attributes
int	out
int	err
int	in

Private Attributes
JFileInputStreamBuffer *	gOut
JFileInputStreamBuffer *	gErr
JFileOutputStreamBuffer *	gIn

Detailed Description

Streaming of input and output from Linux command.

Definition at line 29 of file JProcess.hh.

Constructor & Destructor Documentation

JSYSTEM::JProcess::JProcess ( )

inline

Default constructor.

This constructor starts an interactive shell.

Definition at line 36 of file JProcess.hh.

               :
      out (-1),
      err (-1),
      in  (-1),
      gOut(NULL),
      gErr(NULL),
      gIn (NULL)
    { 
      execute("/bin/tcsh", "tcsh", "-i", "-f");
    }

JSYSTEM::JProcess::JProcess ( const std::string &  command )

inline

Constructor.

Parameters

command

Linux command

Definition at line 53 of file JProcess.hh.

                                       :
      out (-1),
      err (-1),
      in  (-1),
      gOut(NULL),
      gErr(NULL),
      gIn (NULL)
    { 
      execute("/bin/tcsh", "tcsh", "-f", "-c", command.c_str());
    }

JSYSTEM::JProcess::~JProcess ( )

inline

Destructor.

Definition at line 68 of file JProcess.hh.

    {
      close(err);
      close(out);
      close(in);

      if (gOut != NULL) { delete gOut; }
      if (gErr != NULL) { delete gErr; }
      if (gIn  != NULL) { delete gIn;  }
    }

Member Function Documentation

JFileInputStreamBuffer* JSYSTEM::JProcess::getInputStreamBuffer ( const std::size_t  size = 65536 )

inline

Get pointer to input stream buffer connected to the normal output stream.

Parameters

size	size of internal buffers

Returns

pointer input stream buffer

Definition at line 86 of file JProcess.hh.

    {
      if (gOut == NULL) {
        gOut = new JFileInputStreamBuffer(out, size);
      }

      return gOut;
    }

JFileInputStreamBuffer* JSYSTEM::JProcess::getErrorStreamBuffer ( const std::size_t  size = 65536 )

inline

Get pointer to input stream buffer connected to the error output stream.

Parameters

size	size of internal buffers

Returns

pointer to input stream buffer

Definition at line 102 of file JProcess.hh.

    {
      if (gErr == NULL) {
        gErr = new JFileInputStreamBuffer(err, size);
      }

      return gErr;
    }

JFileOutputStreamBuffer* JSYSTEM::JProcess::getOutputStreamBuffer ( const std::size_t  size = 65536 )

inline

Get pointer to output stream buffer connected to the normal input stream.

Parameters

size	size of internal buffers

Returns

pointer to output stream buffer

Definition at line 118 of file JProcess.hh.

    {
      if (gIn == NULL) {
        gIn = new JFileOutputStreamBuffer(in, size);
      }

      return gIn;
    }

void JSYSTEM::JProcess::execute ( const char *  path, const char *  arg0, const char *  arg1 = (char*) NULL, const char *  arg2 = (char*) NULL, const char *  arg3 = (char*) NULL, const char *  arg4 = (char*) NULL, const char *  arg5 = (char*) NULL, const char *  arg6 = (char*) NULL, const char *  arg7 = (char*) NULL, const char *  arg8 = (char*) NULL, const char *  arg9 = (char*) NULL  )

inlineprotected

Execute command.

Parameters

path	path
arg0	comma separted argument list
arg1	comma separted argument list
arg2	comma separted argument list
arg3	comma separted argument list
arg4	comma separted argument list
arg5	comma separted argument list
arg6	comma separted argument list
arg7	comma separted argument list
arg8	comma separted argument list
arg9	comma separted argument list

Definition at line 143 of file JProcess.hh.

    {
      int pipe_stdin [2];
      int pipe_stdout[2];
      int pipe_stderr[2];

      if (pipe(pipe_stdin))  { throw JPipeOpenException("Error at pipe of standard input.");  }
      if (pipe(pipe_stdout)) { throw JPipeOpenException("Error at pipe of standard output."); }
      if (pipe(pipe_stderr)) { throw JPipeOpenException("Error at pipe of standard error.");  }
      
      const pid_t pid = fork();

      if (pid < 0) 

        // error

        throw JForkException("JProcess::fork() failed");

      else if (pid == 0) {

        // child

        close(pipe_stdin [1]);
        if (dup2 (pipe_stdin [0], STDIN_FILENO)  == -1) { JSystemException("dup2-stdin"); }

        close(pipe_stdout[0]);
        if (dup2 (pipe_stdout[1], STDOUT_FILENO) == -1) { JSystemException("dup2-stdout"); }

        close(pipe_stdout[0]);
        if (dup2 (pipe_stdout[1], STDERR_FILENO) == -1) { JSystemException("dup2-stderr"); }

        execl(path, arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9, (char*) NULL);

        throw JSystemException(path);

      } else {

        // parent

        in  = pipe_stdin [1];
        out = pipe_stdout[0];
        err = pipe_stderr[0];

        close(pipe_stdin [0]);
        close(pipe_stdout[1]);
        close(pipe_stderr[1]);
      }
    }

Member Data Documentation

int JSYSTEM::JProcess::out

protected

Definition at line 202 of file JProcess.hh.

int JSYSTEM::JProcess::err

protected

Definition at line 203 of file JProcess.hh.

int JSYSTEM::JProcess::in

protected

Definition at line 204 of file JProcess.hh.

JFileInputStreamBuffer* JSYSTEM::JProcess::gOut

private

Definition at line 207 of file JProcess.hh.

JFileInputStreamBuffer* JSYSTEM::JProcess::gErr

private

Definition at line 208 of file JProcess.hh.

JFileOutputStreamBuffer* JSYSTEM::JProcess::gIn

private

Definition at line 209 of file JProcess.hh.

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

• JProcess.hh