我正在用C编写一个简单的应用程序，我想在BSD许可下发布它。该应用程序的一部分负责将有关该程序的信息输出到其用户。但是，我在打印许可证文本时遇到问题。这是示例：
#include <stdio.h>
#include <stdlib.h>
void show_license(void)
{
const char *license = "\n\
Copyright (c) 2012 \n\
All rights reserved.\n\
\"Redistribution and use in source and binary forms, with or without\n\
modification, are permitted provided that the following conditions are\n\
met:\n\
\n\
* Redistributions of source code must retain the above copyright\n\
notice, this list of conditions and the following disclaimer.\n\
* Redistributions in binary form must reproduce the above copyright\n\
notice, this list of conditions and the following disclaimer in\n\
the documentation and/or other materials provided with the\n\
distribution.\n\
* Neither the name of XXX and its Subsidiary(-ies) nor the names\n\
of its contributors may be used to endorse or promote products derived\n\
from this software without specific prior written permission.\n\
\n\
\n\
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n\
\"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\n\
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\n\
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\n\
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\n\
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\n\
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\n\
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\n\
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n\
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n\
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\"\n\
\n\
\n\ \n";
fputs("\n", stderr);
fputs(license, stderr);
fputs("\n", stderr);
}
int main()
{
show_license();
return 0;
}
我gcc (Ubuntu/Linaro 4.8.1-10ubuntu9) 4.8.11在Kubuntu 13.10上使用编译我的应用程序。我收到此警告消息：
warning: unknown escape sequence: '\040' [enabled by default]
const char *license = "\n\
^
我该如何摆脱呢？我答应自己写一个没有任何警告和错误的代码。这是一个普通的C应用程序。
编辑：
谢谢大家，这是正常运行的无警告代码：
#include <stdio.h>
#include <stdlib.h>
void show_license(void)
{
const char *license = "\n \
Copyright (c) 2012 \n\
All rights reserved.\n\
\"Redistribution and use in source and binary forms, with or without\n\
modification, are permitted provided that the following conditions are\n\
met:\n\
\n\
* Redistributions of source code must retain the above copyright\n\
notice, this list of conditions and the following disclaimer.\n\
* Redistributions in binary form must reproduce the above copyright\n\
notice, this list of conditions and the following disclaimer in\n\
the documentation and/or other materials provided with the\n\
distribution.\n\
* Neither the name of XXX and its Subsidiary(-ies) nor the names\n\
of its contributors may be used to endorse or promote products derived\n\
from this software without specific prior written permission.\n\
\n\n\
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS\n\
\"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT\n\
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\n\
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT\n\
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,\n\
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT\n\
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,\n\
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY\n\
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT\n\
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE\n\
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.\"\n\
\n\n\n";
fputs("\n", stderr);
fputs(license, stderr);
fputs("\n", stderr);
}
int main()
{
show_license();
return 0;
}