Question

我正在尝试用c程序构建一个shell程序。基本上我需要一个文本文件，其中一遍又一遍地重复相同的shell命令，但更改了一个部分。我尝试构建一个从1到750计数的C程序，并打印出一个更改了一个数字的段落，但它正在尝试读取shell命令并给我错误。我如何忽略shell命令并打印printf中的内容？

以下是该计划：

#include <stdio.h>

int main ()
{
    int x;
    for(x=1;x<751;x++){
        printf("#!/bin/sh");
        printf("NRNHOME="/Applications/NEURON-7.3/nrn"");
        printf("\NEURONHOME="${NRNHOME}/share/nrn"");
        printf("CPU=i386");
        printf("NRNBIN="${NRNHOME}/i386/bin/"");
        printf("PATH="${NRNHOME}/i386/bin:${PATH}"");
        printf("export NRNHOME");
        printf("export NEURONHOME");
        printf("export NRNBIN");
        printf("export PATH");
        printf("export CPU");
        printf("nrncarbon=yes");
        printf("export nrncarbon");
        printf("cd "\${NRNHOME}/i386/bin"");
        printf("./nrngui.sh "/Applications/NSD2013/s%d.hoc"\n\n",x);
    }
}

它告诉我所有的目录都是未申报的，它预计a）在$之前？我想要的是打印出更改.hoc文件的命令，这些命令在最后一行以s1.hoc开头并以s750.hoc结尾。

提前感谢您的建议。

Answer 1

除了你的程序将生成一个相对无用的长输出列表，其中750个几乎相同的脚本，你可能需要在750个单独的脚本文件中进行切换，有一些具体问题导致它出现故障：

    printf("#!/bin/sh");

因为这个语句在循环内部，所以它将是
printf不会自行添加换行符，如果您希望下一个printf在新行开头，请添加\n
```
printf("\NEURONHOME="${NRNHOME}/share/nrn"");
```
非常确定\N一开始是无意的
字符串中的双引号应该被转义，例如\"
```
printf("cd "\${NRNHOME}/i386/bin"");
```

不确定为什么你似乎逃脱了这里的$ ...

    printf("./nrngui.sh "/Applications/NSD2013/s%d.hoc"\n\n",x);
}

无论如何，在纯shellcript中执行此操作非常容易，并且在1次打击中将输出发送到750个不同的脚本文件：

for i in {1..750}  ; do
cat << EOT > the_output_script$i.sh
#!/bin/sh
NRNHOME="/Applications/NEURON-7.3/nrn"
...      
# If you want bash to ignore variables that should be evaluated later on
# you just need to escape the dollarsign
NRNBIN="\${NRNHOME}/i386/bin/"
./nrngui.sh "/Applications/NSD2013/s$i.hoc
EOT
# we're after the end of the heredoc, so here we can add other stuff that
# needs to be done in the loop, like changing the file's access:
chown ug+x the_output_script$i.sh
done

将生成750个名为the_output_script1.sh的文件到the_output_script750.sh，这是我认为你真正想要的。顺便说一句，这个脚本中使用的核心技巧叫做heredoc or here document

Answer 2

好的，保持原意（仅限教育用途）：

#include <stdio.h>

int main ()
{
    int x;

    for(x=1;x<751;x++) {
        printf("#!/bin/sh\n");
        printf("NRNHOME=\"/Applications/NEURON-7.3/nrn\"\n");
        printf("NEURONHOME=\"${NRNHOME}/share/nrn\"\n");
        printf("CPU=i386");
        printf("NRNBIN=\"${NRNHOME}/i386/bin/\"\n");
        printf("PATH=\"${NRNHOME}/i386/bin:${PATH}\"\n");
        printf("export NRNHOME");
        printf("export NEURONHOME");
        printf("export NRNBIN");
        printf("export PATH");
        printf("export CPU");
        printf("nrncarbon=yes");
        printf("export nrncarbon");
        printf("cd \"${NRNHOME}/i386/bin\"\n");
        printf("./nrngui.sh \"/Applications/NSD2013/s%d.hoc\"\n\n",x);
    }
}

现在，另一种方法是（my_script.sh）：

#!/bin/sh
NRNHOME=/Applications/NEURON-7.3/nrn
NEURONHOME=${NRNHOME}/share/nrn
CPU=i386
NRNBIN=${NRNHOME}/i386/bin/
PATH=${NRNHOME}/i386/bin:${PATH}
export NRNHOME
export NEURONHOME
export NRNBIN
export PATH
export CPU
nrncarbon=yes
export nrncarbon
cd ${NRNHOME}/i386/bin
./nrnqui.sh /Applications/NSD2013/s*.hoc // the lazy way

OR：my_script.sh：//带有for循环

#!/bin/sh
NRNHOME=/Applications/NEURON-7.3/nrn
NEURONHOME=${NRNHOME}/share/nrn
CPU=i386
NRNBIN=${NRNHOME}/i386/bin/
PATH=${NRNHOME}/i386/bin:${PATH}
export NRNHOME
export NEURONHOME
export NRNBIN
export PATH
export CPU
nrncarbon=yes
export nrncarbon
cd ${NRNHOME}/i386/bin
for i in {1..750}
do
    ./nrnqui.sh /Applications/NSD2013/s{$i}.hoc
done

Answer 3

这可以做到，

#include <stdio.h>

int main ()
{
    int x;
    for(x=1;x<751;x++){
        printf("#!/bin/sh\n");
        printf("NRNHOME=\"/Applications/NEURON-7.3/nrn\"\n");
        printf("NEURONHOME=\"${NRNHOME}/share/nrn\"\n");
        printf("CPU=i386\n");
        printf("NRNBIN=\"${NRNHOME}/i386/bin/\"\n");
        printf("PATH=\"${NRNHOME}/i386/bin:${PATH}\"\n");
        printf("export NRNHOME\n");
        printf("export NEURONHOME\n");
        printf("export NRNBIN\n");
        printf("export PATH\n");
        printf("export CPU\n");
        printf("nrncarbon=yes\n");
        printf("export nrncarbon\n");
        printf("cd \"${NRNHOME}/i386/bin\"\n");
        printf("./nrngui.sh \"/Applications/NSD2013/s%d.hoc\"\n\n",x);
    }
}

我强烈建议您学习printf here。请参阅here给出的来源了解c语言

使用printf（）在C中打印shell命令行

3 个答案: