Tcl_GetOpenFile(3) Tcl Library Procedures Tcl_GetOpenFile(3)_________________________________________________________________NAMETcl_GetOpenFile - Get a standard IO File * handle from a
channel.
SYNOPSIS
#include <tcl.h>
int
Tcl_GetOpenFile(interp, string, write, checkUsage, filePtr)
ARGUMENTS
Tcl_Interp *interp (in) Tcl interpreter from
which file handle is
to be obtained.
char *string (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 read-
ing.
int checkUsage (in) If non-zero, then an
error will be gener-
ated if the file
wasn't 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
string.
_________________________________________________________________DESCRIPTIONTcl_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. string didn't make any
sense or checkUsage was set and the file wasn't opened for
Tcl 7.5 1
Tcl_GetOpenFile(3) Tcl Library Procedures Tcl_GetOpenFile(3)
the access specified by write) then TCL_ERROR is returned
and interp->result will contain an error message. In the
current implementation checkUsage is ignored and consis-
tency checks are always performed.
KEYWORDS
channel, file handle, permissions, pipeline, read, write
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