Troubles with pipes, fork, and dup2 Post: 302873041

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filter_create_fd

filter_create_fd(3)						   util/filter.h					       filter_create_fd(3)

NAME

       filter_create_fd  - Create a sub process and return the requested pipes

SYNOPSIS

       #include <util/filter.h>

       NEOERR *filter_create_fd(const char *cmd, int *fdin, int *fdout, int *fderr,
				pid_t *pid);

ARGUMENTS

       cmd -> the sub command to execute.  Will be executed with
       /bin/sh -c
       fdin -> pointer to return the stdin pipe, or NULL if you don't
       want the stdin pipe
       fdout -> pointer to return the stdout pipe, or NULL if you don't
       want the stdout pipe
       fderr -> pointer to return the stderr pipe, or NULL if you don't
       want the stderr pipe

DESCRIPTION

       filter_create_fd and filter_create_fp are what popen

       been:  a  mechanism  to	create sub processes and have pipes to all their input/output.	The concept was taken from mutt, though python has
       something similar with popen3/popen4.  You control which pipes the function returns by the fdin/fdout/fderr arguments.  A NULL value  means
       "don't  create a pipe", a pointer to an int will cause the pipes to be created and the value of the file descriptor stored in the int.  You
       will have to close(2) the file descriptors yourself.

RETURN VALUE

       fdin -> the stdin file descriptor of the sub process
       fdout -> the stdout file descriptor of the sub process
       fderr -> the stderr file descriptor of the sub process
       pid -> the pid of the sub process

SEE ALSO

       filter_wait(3), filter_create_fp(3), filter_create_fd

ClearSilver							   12 July 2007 					       filter_create_fd(3)

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