09-28-2018
For threads started in the Shell Programming and Scripting forum, it always helps if you tell us what operating system and shell you're using.
In what way is the pipeline using tail -f not working.
We have to assume that you now that tail -f will never end and will continue reading from /var/log/mail.info forever, and the greps following that in your pipeline will continue processing data from that file as new lines are written to that file until something external to your pipeline terminates one of the processes in your pipeline. If you don't want the pipeline to run forever waiting for additional data to be written into that file, you shouldn't be using tail's -f option.
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LEARN ABOUT CENTOS
glactiveshaderprogram
GLACTIVESHADERPROGRA(3G) OpenGL Manual GLACTIVESHADERPROGRA(3G)
NAME
glActiveShaderProgram - set the active program object for a program pipeline object
C SPECIFICATION
void glActiveShaderProgram(GLuint pipeline, GLuint program);
PARAMETERS
pipeline
Specifies the program pipeline object to set the active program object for.
program
Specifies the program object to set as the active program pipeline object pipeline.
DESCRIPTION
glActiveShaderProgram sets the linked program named by program to be the active program for the program pipeline object pipeline. The
active program in the active program pipeline object is the target of calls to glUniform() when no program has been made current through a
call to glUseProgram().
ERRORS
GL_INVALID_OPERATION is generated if pipeline is not a name previously returned from a call to glGenProgramPipelines() or if such a name
has been deleted by a call to glDeleteProgramPipelines().
GL_INVALID_OPERATION is generated if program refers to a program object that has not been successfully linked.
SEE ALSO
glGenProgramPipelines(), glDeleteProgramPipelines(), glIsProgramPipeline(), glUseProgram(), glUniform()
COPYRIGHT
Copyright (C) 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication
License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.
AUTHORS
opengl.org
opengl.org 06/10/2014 GLACTIVESHADERPROGRA(3G)