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Full Discussion: Communicate with multiple process using named pipe
Top Forums Programming Communicate with multiple process using named pipe Post 302574521 by Corona688 on Thursday 17th of November 2011 12:17:41 PM
Old 11-17-2011
Create two named pipes with mkfifo("pipename", 0660);

Open them with
Code:
int readfd=open("pipename", O_RDONLY);

Code:
int writefd=open("pipename", O_WRONLY);

Be sure to open them in the same order in both processes. When you open the pipe for read in one, it will wait for the other process to open it for write before finishing.

Write to it with write(fd, buffer, size), read from it with read(fd, buffer, size)
 

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LEARN ABOUT SUSE

pfsinmulti

pfsinmulti(1)						      General Commands Manual						     pfsinmulti(1)

NAME

       pfsinmulti - read several streams of frames and write pfs streams to named pipes

SYNOPSIS

       pfsinmulti pfsinmulti <file> [--frames f:s:t] [--skip-frames] [<file>...] -- command @1 @2 [@3 ...]

DESCRIPTION

       Use  this  command  to read several animation sequences and write them to pfsstreams. This command is useful with those pfs programs, which
       take several pfs streams as arguments. For example, the following command can be used to combine two animations so that there are  stitched
       together:

	 pfsinmulti anim_a-%04d.hdr anim_b-%04d.hdr -- pfscat @1 @2

       arguments  @1 and @2 are replaced with named pipes for anim_a-%04d.hdr and anim_b-%04d.hdr frames respectively. command argument is obliga-
       tory and it must be preceded with '--'. There should be as many @1, @2, .., @n arguments as there are animation sequences given as input.

       Arguments --frames, --skip-frames and other options are handled the same way as in pfsin program. Also pfsinmulti recognizes the same  file
       formats as pfsin.

       Technically,  pfsinmulti creates a named pipe for each pfsstream, replaces @n arguments with the names of those pipes and deletes the pipes
       when command finishes.

EXAMPLES

       pfsinmulti image1.hdr image2.hdr -- cat @1 @2 | pfsview

	      Does the same as 'pfsv image1.hdr image2.hdr' but in much more sophisticated way.

SEE ALSO

       pfsin(1)

BUGS

       This command currently does not handle multiple frames given with a %d pattern in case of LDR formats: JPEG, PNG, PNM.

       Please report bugs and comments to Rafal Mantiuk <mantiuk@mpi-sb.mpg.de>.

																     pfsinmulti(1)
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