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
