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Full Discussion: Trouble with tail and grep
Top Forums Shell Programming and Scripting Trouble with tail and grep Post 303024069 by Don Cragun on Friday 28th of September 2018 06:50:48 AM
Old 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 DEBIAN

gluseprogramstages

GLUSEPROGRAMSTAGES(3G)						  [FIXME: manual]					    GLUSEPROGRAMSTAGES(3G)

NAME

       glUseProgramStages - bind stages of a program object to a program pipeline

C SPECIFICATION

       void glUseProgramStages(GLuint pipeline, GLbitfield stages, GLuint program);

PARAMETERS

       pipeline
	   Specifies the program pipeline object to which to bind stages from program.

       stages
	   Specifies a set of program stages to bind to the program pipeline object.

       program
	   Specifies the program object containing the shader executables to use in pipeline.

DESCRIPTION

       glUseProgramStages binds executables from a program object associated with a specified set of shader stages to the program pipeline object
       given by pipeline.  pipeline specifies the program pipeline object to which to bind the executables.  stages contains a logical combination
       of bits indicating the shader stages to use within program with the program pipeline object pipeline.  stages must be a logical combination
       of GL_VERTEX_SHADER_BIT, GL_TESS_CONTROL_SHADER_BIT, GL_TESS_EVALUATION_SHADER_BIT, GL_GEOMETRY_SHADER_BIT, and GL_FRAGMENT_SHADER_BIT.
       Additionally, the special value GL_ALL_SHADER_BITS may be specified to indicate that all executables contained in program should be
       installed in pipeline.

       If program refers to a program object with a valid shader attached for an indicated shader stage, glUseProgramStages installs the
       executable code for that stage in the indicated program pipeline object pipeline. If program is zero, or refers to a program object with no
       valid shader executable for a given stage, it is as if the pipeline object has no programmable stage configured for the indicated shader
       stages. If stages contains bits other than those listed above, and is not equal to GL_ALL_SHADER_BITS, an error is generated.

ERRORS

       GL_INVALID_VALUE is generated if shaders contains set bits that are not recognized, and is not the reserved value GL_ALL_SHADER_BITS.

       GL_INVALID_OPERATION is generated if program refers to a program object that was not linked with its GL_PROGRAM_SEPARABLE status set.

       GL_INVALID_OPERATION is generated if program refers to a program object that has not been successfully linked.

       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().

SEE ALSO

       glGenProgramPipelines(), glDeleteProgramPipelines(), glIsProgramPipeline()

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/.

[FIXME: source] 						    05/30/2012						    GLUSEPROGRAMSTAGES(3G)
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