TclFile
TclpOpenFile(
const char *fname, /* The name of the file to open. */
int mode) /* In what mode to open the file? */
{
int fd;
const char *native;
Tcl_DString ds;
native = Tcl_UtfToExternalDString(NULL, fname, -1, &ds);
fd = TclOSopen(native, mode, 0666); /* INTL: Native. */
Tcl_DStringFree(&ds);
if (fd != -1) {
fcntl(fd, F_SETFD, FD_CLOEXEC);
/*
* If the file is being opened for writing, seek to the end so we can
* append to any data already in the file.
*/
if ((mode & O_WRONLY) && !(mode & O_APPEND)) {
TclOSseek(fd, (Tcl_SeekOffset) 0, SEEK_END);
}
/*
* Increment the fd so it can't be 0, which would conflict with the
* NULL return for errors.
*/
return MakeFile(fd);
}
return NULL;
}
Tcl_Channel
TclpOpenFileChannel(
Tcl_Interp *interp, /* Interpreter for error reporting; can be
* NULL. */
Tcl_Obj *pathPtr, /* Name of file to open. */
int mode, /* POSIX open mode. */
int permissions) /* If the open involves creating a file, with
* what modes to create it? */
{
int fd, channelPermissions;
FileState *fsPtr;
const char *native, *translation;
char channelName[16 + TCL_INTEGER_SPACE];
const Tcl_ChannelType *channelTypePtr;
switch (mode & (O_RDONLY | O_WRONLY | O_RDWR)) {
case O_RDONLY:
channelPermissions = TCL_READABLE;
break;
case O_WRONLY:
channelPermissions = TCL_WRITABLE;
break;
case O_RDWR:
channelPermissions = (TCL_READABLE | TCL_WRITABLE);
break;
default:
/*
* This may occurr if modeString was "", for example.
*/
Tcl_Panic("TclpOpenFileChannel: invalid mode value");
return NULL;
}
native = Tcl_FSGetNativePath(pathPtr);
if (native == NULL) {
if (interp != (Tcl_Interp *) NULL) {
Tcl_AppendResult(interp, "couldn't open \"",
TclGetString(pathPtr), "\": filename is invalid on this platform",
NULL);
}
return NULL;
}
#ifdef DJGPP
SET_BITS(mode, O_BINARY);
#endif
fd = TclOSopen(native, mode, permissions);
if (fd < 0) {
if (interp != NULL) {
Tcl_SetObjResult(interp, Tcl_ObjPrintf(
"couldn't open \"%s\": %s",
TclGetString(pathPtr), Tcl_PosixError(interp)));
}
return NULL;
}
/*
* Set close-on-exec flag on the fd so that child processes will not
* inherit this fd.
*/
fcntl(fd, F_SETFD, FD_CLOEXEC);
sprintf(channelName, "file%d", fd);
#ifdef SUPPORTS_TTY
if (strcmp(native, "/dev/tty") != 0 && isatty(fd)) {
/*
* Initialize the serial port to a set of sane parameters. Especially
* important if the remote device is set to echo and the serial port
* driver was also set to echo -- as soon as a char were sent to the
* serial port, the remote device would echo it, then the serial
* driver would echo it back to the device, etc.
*
* Note that we do not do this if we're dealing with /dev/tty itself,
* as that tends to cause Bad Things To Happen when you're working
* interactively. Strictly a better check would be to see if the FD
* being set up is a device and has the same major/minor as the
* initial std FDs (beware reopening!) but that's nearly as messy.
*/
translation = "auto crlf";
channelTypePtr = &ttyChannelType;
TtyInit(fd);
} else
#endif /* SUPPORTS_TTY */
{
translation = NULL;
channelTypePtr = &fileChannelType;
}
fsPtr = ckalloc(sizeof(FileState));
fsPtr->validMask = channelPermissions | TCL_EXCEPTION;
fsPtr->fd = fd;
fsPtr->channel = Tcl_CreateChannel(channelTypePtr, channelName,
fsPtr, channelPermissions);
if (translation != NULL) {
/*
* Gotcha. Most modems need a "\r" at the end of the command sequence.
* If you just send "at\n", the modem will not respond with "OK"
* because it never got a "\r" to actually invoke the command. So, by
* default, newlines are translated to "\r\n" on output to avoid "bug"
* reports that the serial port isn't working.
*/
if (Tcl_SetChannelOption(interp, fsPtr->channel, "-translation",
translation) != TCL_OK) {
Tcl_Close(NULL, fsPtr->channel);
return NULL;
}
}
return fsPtr->channel;
}