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Full Discussion: Pipe problem
Top Forums Programming Pipe problem Post 302247873 by isato on Thursday 16th of October 2008 02:08:49 PM
Old 10-16-2008
Quote:
Originally Posted by shamrock
You're not capturing the return value of the dupPipe function in main() outlined in red. The newly created destfd is lost so you can't connect the two processes together.
I think I have figured it out. I am creating a new pipe for every process in the for -loop( not shown in the code).
I am not anymore.


Now I am able to do for example ls|wc. but I have to finish whit an Enter. I think it has to do whit not closed pipe ends in parent.
 

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EXECUTE(7)                                                         SQL Commands                                                         EXECUTE(7)

NAME
EXECUTE - execute a prepared statement SYNOPSIS
EXECUTE name [ ( parameter [, ...] ) ] DESCRIPTION
EXECUTE is used to execute a previously prepared statement. Since prepared statements only exist for the duration of a session, the pre- pared statement must have been created by a PREPARE statement executed earlier in the current session. If the PREPARE statement that created the statement specified some parameters, a compatible set of parameters must be passed to the EXECUTE statement, or else an error is raised. Note that (unlike functions) prepared statements are not overloaded based on the type or number of their parameters; the name of a prepared statement must be unique within a database session. For more information on the creation and usage of prepared statements, see PREPARE [prepare(7)]. PARAMETERS
name The name of the prepared statement to execute. parameter The actual value of a parameter to the prepared statement. This must be an expression yielding a value that is compatible with the data type of this parameter, as was determined when the prepared statement was created. OUTPUTS
The command tag returned by EXECUTE is that of the prepared statement, and not EXECUTE. EXAMPLES
Examples are given in the Examples [prepare(7)] section of the PREPARE [prepare(7)] documentation. COMPATIBILITY
The SQL standard includes an EXECUTE statement, but it is only for use in embedded SQL. This version of the EXECUTE statement also uses a somewhat different syntax. SEE ALSO
DEALLOCATE [deallocate(7)], PREPARE [prepare(7)] SQL - Language Statements 2010-05-14 EXECUTE(7)
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