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Passing struct through unix pipe -solved

 
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Old 03-06-2010
Passing struct through unix pipe -solved
EDIT: Nevermind, called a friend who is good at this stuff and he figured it out Smilie

Hi all,

So I'm trying to teach myself to write programs for unix in c. I am currently creating a program, and I need to pass a struct through a pipe, but I can't figure out how.

The struct I want to pass has two types in it, one enum and one union of two other structs. These two other structs each contain an int and a char variablename[256] array.

gcc won't let me just pass the struct using write(pipefd[1], struct, size_of_struct) since the struct is not a char buffer. So that's my question...how does one go about passing a struct?

Thanks!

EDIT: Nevermind, called a friend who is good at this stuff and he figured it out Smilie
Last edited by twnsfn34; 03-06-2010 at 10:51 PM..
 
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LEARN ABOUT PLAN9

pipe

PIPE(2) 							System Calls Manual							   PIPE(2)

NAME

       pipe - create an interprocess channel

SYNOPSIS

       #include <u.h>
       #include <libc.h>

       int pipe(int fd[2])

DESCRIPTION

       Pipe  creates  a  buffered  channel for interprocess I/O communication.	Two file descriptors are returned in fd.  Data written to fd[1] is
       available for reading from fd[0] and data written to fd[0] is available for reading from fd[1].

       After the pipe has been established, cooperating processes created by subsequent fork(2) calls may pass data through the pipe with read and
       write  calls.   The bytes placed on a pipe by one write are contiguous even if many processes are writing.  Write boundaries are preserved:
       each read terminates when the read buffer is full or after reading the last byte of a write, whichever comes first.

       The number of bytes available to a read(2) is reported in the Length field returned by fstat or dirfstat on a pipe (see stat(2)).

When all the data has been read from a pipe and the writer has closed the pipe or exited,
       read(2) will return 0 bytes.  Writes to a pipe with no reader will generate a note sys: write on closed pipe.

SOURCE

       /sys/src/libc/9syscall

SEE ALSO

       intro(2), read(2), pipe(3)

DIAGNOSTICS

       Sets errstr.

BUGS

       If a read or a write of a pipe is interrupted, some unknown number of bytes may have been transferred.
       When a read from a pipe returns 0 bytes, it usually means end of file but is indistinguishable from reading the result of an explicit write
       of zero bytes.

																	   PIPE(2)