egd_acq_setup(3) [debian man page]

EGD_ACQ_SETUP(3)					       EEGDEV library manual						  EGD_ACQ_SETUP(3)

NAME

       egd_acq_setup - specify which and how channel data should be obtained

SYNOPSIS

       #include <eegdev.h>

       int egd_acq_setup(struct eegdev* dev,
			 unsigned int narr, const size_t *strides,
			 unsigned int ngrp, const struct grpconf *grp);

DESCRIPTION

       egd_acq_setup() configures the way data is provided by the device referenced by dev for the next calls to egd_get_data(3).

       The  narr  argument specifies the number of buffers that will be supplied in the argument list of egd_get_data(3). strides should points to
       an array of narr values specifying respectively for each buffers its stride, i.e. the size in bytes between the data of two successive sam-
       ples in this buffer.

       The  channels  data  that  must	be  returns in those buffers are defined by ngrp groups of consecutive channels. The groups definition are
       passed by grp which points to an array of ngrp structures, defined as follows:

	   struct grpconf {
	       unsigned int sensortype;    /* type of channel */
	       unsigned int index;	   /* index of the first channel */
	       unsigned int nch;	   /* number of channels */
	       unsigned int iarray;	   /* index of the array */
	       unsigned int arr_offset;    /* offset in the array */
	       unsigned int datatype;	   /* type in the array */
	   };

       The different fields in the structure defines the properties of the group:

	* sensortype specifies the type of channel. it must one of the following values returned by egd_sensor_type(3).

	* index indicates the index of the first channel in the group. Note that channel index i refers the i-th channel  of  the  type  specified
	  previously, i.e. the channel index i refers to two differents channels if sensortype differs.

	* nch specifies the number of consecutive channels that should be in the group.

	* iarray indicates which buffer the data of the channel group must be written to.

	* arr_offset defines the offset of the memory location of the data in the buffers relatively to the beginning of each sample.

	* datatype  specifies  the type of data that must be written to the buffer. It must be one of the following value: EGD_INT32, EGD_FLOAT or
	  EGD_DOUBLE

RETURN VALUE

       The function returns 0 in case of succes. Otherwise, -1 is returned and errno is set accordingly.

ERRORS

       egd_acq_setup() will fail if:

       EINVAL dev is NULL.

       EPERM  The acquisition is running

THREAD SAFETY

       egd_acq_setup() is thread-safe.

EXAMPLE

       See egd_get_data(3) for a example

SEE ALSO

       egd_get_data(3), egd_start(3), egd_sensor_type(3)

EPFL
								       2010							  EGD_ACQ_SETUP(3)

Tcl_GetStdChannel(3)					      Tcl Library Procedures					      Tcl_GetStdChannel(3)

__________________________________________________________________________________________________________________________________________________

NAME

       Tcl_GetStdChannel, Tcl_SetStdChannel - procedures for retrieving and replacing the standard channels

SYNOPSIS

       #include <tcl.h>

       Tcl_Channel
       Tcl_GetStdChannel(type)

       Tcl_SetStdChannel(channel, type)

ARGUMENTS

       int	     type      (in)	 The  identifier for the standard channel to retrieve or modify.  Must be one of TCL_STDIN, TCL_STDOUT, or
					 TCL_STDERR.

       Tcl_Channel   channel   (in)	 The channel to use as the new value for the specified standard channel.
_________________________________________________________________

DESCRIPTION

       Tcl defines three special channels that are used by various I/O related commands if no other channels are specified.   The  standard  input
       channel	has  a	channel name of stdin and is used by read and gets.  The standard output channel is named stdout and is used by puts.  The
       standard error channel is named stderr and is used for reporting errors.  In addition, the standard channels are  inherited  by	any  child
       processes created using exec or open in the absence of any other redirections.

       The  standard  channels	are  actually  aliases	for  other normal channels.  The current channel associated with a standard channel can be
       retrieved by calling Tcl_GetStdChannel with one of TCL_STDIN, TCL_STDOUT, or TCL_STDERR as the type.  The return  value	will  be  a  valid
       channel, or NULL.

       A  new channel can be set for the standard channel specified by type by calling Tcl_SetStdChannel with a new channel or NULL in the channel
       argument.  If the specified channel is closed by a later call to Tcl_Close, then the corresponding standard channel will  automatically	be
       set to NULL.

       If  Tcl_GetStdChannel  is called before Tcl_SetStdChannel, Tcl will construct a new channel to wrap the appropriate platform-specific stan-
       dard file handle.  If Tcl_SetStdChannel is called before Tcl_GetStdChannel, then the default channel will not be created.

       If one of the standard channels is set to NULL, either by calling Tcl_SetStdChannel with a NULL channel argument, or by	calling  Tcl_Close
       on  the	channel,  then	the next call to Tcl_CreateChannel will automatically set the standard channel with the newly created channel.	If
       more than one standard channel is NULL, then the standard channels will be assigned starting with standard input, followed by standard out-
       put, with standard error being last.

       See Tcl_StandardChannels for a general treatise about standard channels and the behaviour of the Tcl library with regard to them.

SEE ALSO

       Tcl_Close(3), Tcl_CreateChannel(3), Tcl_Main(3), tclsh(1)

KEYWORDS

       standard channel, standard input, standard output, standard error

Tcl									7.5						      Tcl_GetStdChannel(3)