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Full Discussion: question about popen in C
Top Forums Programming question about popen in C Post 302504576 by omega666 on Tuesday 15th of March 2011 12:14:36 AM
Old 03-15-2011
so the returns statements are like this: (unless i did something wrong again)
return fdopen(fd[0], "r");
return fdopen(fd[1], "w");
respectively


and just to be clear again, when given 'w', the output of the string gets discarded or printed to stdout?
 

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rm(1)							      General Commands Manual							     rm(1)

Name
       rm, rmdir - remove (unlink) files or directories

Syntax
       rm [-f] [-r] [-i] [-] file-or-directory-name...
       rmdir directory-name...

Description
       The command removes the entries for one or more files from a directory.	If there are no links to the file then the file is destroyed.  For
       further information, see

       The command removes entries for the named directories, which must be empty.  If they are not empty, the directories remain, and displays an
       error message (see EXAMPLES).

       To  remove  a file, you must have write permission in its directory, but you do not need read or write permission on the file itself.  When
       you are using from a terminal, and you do not have write permission on the file, the command asks for confirmation  before  destroying  the
       file.

       If  input  is redirected from the standard input device (your terminal), then checks to ensure that input is not coming from your terminal.
       If not, sets the -f option, which overrides the file protection, and removes the files silently, regardless of what you have  specified	in
       the file redirected as input to See EXAMPLES.

Options
       -    Specifies that the named files have names beginning with a minus (for example ).

       -f   Forces the removal of file or directory without first requesting confirmation.  Only system or usage messages are displayed.

       -i   Prompts  for yes or no response before removing each entry.  Does not ask when combined with the -f option.  If you type a y, followed
	    by any combination of characters, a yes response is assumed.

       -r   Recursively removes all entries from the specified directory and, then, removes the entry for that directory from  its  parent  direc-
	    tory.

Examples
       The following example shows how to remove a file in your current working directory.
       rm myfile
       This example shows use of the null option to remove a file beginning with a minus sign.
       rm - -gorp
       This example shows how a confirmation is requested for removal of a file for which you do not have write permission.
       rm testfile
       rm: override protection 400 for testfile? y
       This  example  shows  how  the combination of -i and -r options lets you examine all the files in a directory before removing them.  In the
       example, mydirectory is a subdirectory of the current working directory.  Note that the last question requests confirmation before removing
       the  directory  itself.	 Although  the user types ``y'', requesting removal of the directory, the command does not allow this, because the
       directory is not empty; the user typed ``n'' to the question about the file file2 , so file2 was not removed.
       rm -ir mydirectory
       rm: remove mydirectory/file1? y
       rm: remove mydirectory/file2? n
	     .
	     .
	     .
       rm: remove mydirectory? y
       rm: mydirectory: Directory not empty
       This example illustrates that overrides file protection when input is redirected from the standard input device.  The user creates  a  file
       named ``alfie'', with a read-only file protection.  The user then creates a file named ``ans'' to contain the character ``n''.  The command
       following destroys the file ``alfie'', even though the redirected input file requested no deletion.
       cat > alfie
       hello
       ^d
       chmod 444 alfie
       cat > ans
       n
       ^d
       rm < ans alfie

See Also
       unlink(2)

																	     rm(1)
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