本文整理汇总了C++中DEVICE::truncate方法的典型用法代码示例。如果您正苦于以下问题：C++ DEVICE::truncate方法的具体用法？C++ DEVICE::truncate怎么用？C++ DEVICE::truncate使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类DEVICE的用法示例。
在下文中一共展示了DEVICE::truncate方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: write_new_volume_label_to_dev
/*
* Write a Volume Label
* !!! Note, this is ONLY used for writing
* a fresh volume label. Any data
* after the label will be destroyed,
* in fact, we write the label 5 times !!!!
*
* This routine should be used only when labeling a blank tape.
*/
bool write_new_volume_label_to_dev(DCR *dcr, const char *VolName,
const char *PoolName, bool relabel)
{
JCR *jcr = dcr->jcr;
DEVICE *dev = dcr->dev;
DEV_BLOCK *block = dcr->block;
Dmsg0(150, "write_volume_label()\n");
if (*VolName == 0) {
Pmsg0(0, "=== ERROR: write_new_volume_label_to_dev called with NULL VolName\n");
goto bail_out;
}
if (relabel) {
volume_unused(dcr); /* mark current volume unused */
/* Truncate device */
if (!dev->truncate(dcr)) {
goto bail_out;
}
if (!dev->is_tape()) {
dev->close(dcr); /* make sure file closed for rename */
}
}
/* Set the new filename for open, ... */
dev->setVolCatName(VolName);
dcr->setVolCatName(VolName);
Dmsg1(150, "New VolName=%s\n", VolName);
if (!dev->open(dcr, OPEN_READ_WRITE)) {
/* If device is not tape, attempt to create it */
if (dev->is_tape() || !dev->open(dcr, CREATE_READ_WRITE)) {
Jmsg3(jcr, M_WARNING, 0, _("Open device %s Volume \"%s\" failed: ERR=%s\n"),
dev->print_name(), dcr->VolumeName, dev->bstrerror());
goto bail_out;
}
}
Dmsg1(150, "Label type=%d\n", dev->label_type);
/*
* Let any stored plugin know that we are about to write a new label to the volume.
*/
if (generate_plugin_event(jcr, bsdEventLabelWrite, dcr) != bRC_OK) {
Dmsg0(200, "Error from bsdEventLabelWrite plugin event.\n");
goto bail_out;
}
for ( ;; ) {
empty_block(block);
if (!dev->rewind(dcr)) {
Dmsg2(130, "Bad status on %s from rewind: ERR=%s\n", dev->print_name(), dev->print_errmsg());
if (!forge_on) {
goto bail_out;
}
}
/* Temporarily mark in append state to enable writing */
dev->set_append();
/* Create PRE_LABEL */
create_volume_label(dev, VolName, PoolName);
/*
* If we have already detected an ANSI label, re-read it
* to skip past it. Otherwise, we write a new one if
* so requested.
*/
if (dev->label_type != B_BAREOS_LABEL) {
if (read_ansi_ibm_label(dcr) != VOL_OK) {
dev->rewind(dcr);
goto bail_out;
}
} else if (!write_ansi_ibm_labels(dcr, ANSI_VOL_LABEL, VolName)) {
goto bail_out;
}
create_volume_label_record(dcr, dev, dcr->rec);
dcr->rec->Stream = 0;
dcr->rec->maskedStream = 0;
if (!write_record_to_block(dcr, dcr->rec)) {
Dmsg2(130, "Bad Label write on %s: ERR=%s\n", dev->print_name(), dev->print_errmsg());
goto bail_out;
} else {
Dmsg2(130, "Wrote label of %d bytes to %s\n", dcr->rec->data_len, dev->print_name());
}
Dmsg0(130, "Call write_block_to_dev()\n");
if (!dcr->write_block_to_dev()) {
Dmsg2(130, "Bad Label write on %s: ERR=%s\n", dev->print_name(), dev->print_errmsg());
goto bail_out;
}
//.........这里部分代码省略.........