Best way to convert this (bash) to c?

primerib · 03-19-2010, 04:20 PM

I was wondering how to & what the best way to convert this bash command to c would be:

Quote:

linux:$ find /dev/dvb/adapter*/frontend*
/dev/dvb/adapter0/frontend0
/dev/dvb/adapter1/frontend0
/dev/dvb/adapter3/frontend0
/dev/dvb/adapter3/frontend1
linux:~$

Doesn't matter if it's portable, just needs to work in linux. Thanks in advance.

schneidz · 03-19-2010, 04:28 PM

the lazy way would be:
system("find /dev/dvb/adapter*/frontend*")

there is also a readdir() function you can use.

primerib · 03-19-2010, 07:00 PM

Sorry, I should have been more clear. There are other things I need to do to that list. I thought doing the c equivalent of that bash command and putting the results into an array would be the best way. From there I can just cycle through the array and do what I need to each.

Sergei Steshenko · 03-19-2010, 07:07 PM

Quote:

Originally Posted by primerib

Sorry, I should have been more clear. There are other things I need to do to that list. I thought doing the c equivalent of that bash command and putting the results into an array would be the best way. From there I can just cycle through the array and do what I need to each.

The primitive approach is to execute the needed command and redirect its stdout to a file. Then, upon the said command completion, you can open the file by standard "C" means and read it line by line.

tuxdev · 03-20-2010, 02:30 PM

The handy commmand to do so is popen()

Code:

FILE *cmdout = popen("find '/dev/dvb/adapter*/frontend*' -print0");
/* use getdelim() to parse out the filenames reliably */
pclose(cmdout);

I generally prefer using a pure-C approach, because if you need to use system() or popen(), you might as well use Bash or POSIX sh. Why can't it stay Bash?