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Old 02-18-2008, 11:53 PM   #1
anuj_sri
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Registered: Apr 2007
Posts: 4

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Question Problem when use getc function before creating a new process with execve()


Hello,
I am facing a strange problem.
I am using execve() to run a program with new enviornment variables.
before I call execve(), I have to read an input from the user.
When the user types the input, and i read it in my code using gets(); my program works fine, and execve calls other executable as expected.
But if instead of gets() I read user input using getc(), as in
do {
*(pDisp + iCnt++) = getc(stdin);
}while(*(pDisp + (iCnt - 1))!='\n');

then when execve() function is encountered in the code,
execve("./b.out",NULL,c);
It does nothing, it does not call my other executable code.

Any hints ?
 
Old 02-20-2008, 09:29 PM   #2
blackhole54
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Registered: Mar 2006
Posts: 1,896

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Quote:
Originally Posted by anuj_sri View Post
Any hints ?
How about a WAG?

My C is a bit rusty, but I believe gets() will terminate its output with a null character. Your loop terminates it with a newline. I am wondering if this input is used to set up the environment variables for the execve() call and the lack of a null character is tripping things up.
 
  


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