Tcl_GetOpenFile(3) Tcl Library Procedures Tcl_GetOpenFile(3)

____________________________________________________________________________

NAME

Tcl_GetOpenFile - Return a FILE* for a channel registered in the
given interpreter (Unix only)

SYNOPSIS

#include <tcl.h>

int
Tcl_GetOpenFile(interp, chanID, write, checkUsage, filePtr)

ARGUMENTS

Tcl_Interp *interp (in) Tcl interpreter from which file
handle is to be obtained.

const char *chanID (in) String identifying channel, such
as stdin or file4.

int write (in) Non-zero means the file will be
used for writing, zero means it
will be used for reading.

int checkUsage (in) If non-zero, then an error will
be generated if the file was not
opened for the access indicated
by write.

ClientData *filePtr (out) Points to word in which to store
pointer to FILE structure for the
file given by chanID.
____________________________________________________________________________

DESCRIPTION

Tcl_GetOpenFile takes as argument a file identifier of the form
returned by the open command and returns at *filePtr a pointer to the
FILE structure for the file. The write argument indicates whether
the FILE pointer will be used for reading or writing. In some cases,
such as a channel that connects to a pipeline of subprocesses,
different FILE pointers will be returned for reading and writing.
Tcl_GetOpenFile normally returns TCL_OK. If an error occurs in
Tcl_GetOpenFile (e.g. chanID did not make any sense or checkUsage was
set and the file was not opened for the access specified by write)
then TCL_ERROR is returned and the interpreter's result will contain
an error message. In the current implementation checkUsage is
ignored and consistency checks are always performed.

Note that this interface is only supported on the Unix platform.

KEYWORDS

channel, file handle, permissions, pipeline, read, write

Tcl 8.0 Tcl_GetOpenFile(3)