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Full Discussion: Redirecting stdin/stdout to/from command from/to string
Top Forums Shell Programming and Scripting Redirecting stdin/stdout to/from command from/to string Post 302403683 by doc_cypher on Saturday 13th of March 2010 11:11:29 PM
Old 03-14-2010
Question Redirecting stdin/stdout to/from command from/to string
Hi,
I am working on a project where I have to generate and execute nasm code on-the-fly. I generate the code in a file program.asm and then execute it.This output is to stdout which i redirect to an output file which i read back to compare results:
system("nasm -f elf program.asm > output");
The problem is I have to do this process (generate code and execute) a lot of times each time i run my program which slows the execution time due to so much file I/O.

Is there some shell trick by which I can generate my code in a string buffer (instead of the file program.asm) and pass it as input to nasm.
Similarly, can I capture the output of nasm into another string buffer without writing it to a file.

Same applies for compiling c programs using gcc. Can my c program be present in a string which i then compile using gcc by redirecting its input from a file to the string. Likewise, can i redirect the output of my c program to a string instead of stdout or any other file before.
 

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LEARN ABOUT DEBIAN

gpiv_mktestimg

GPIV_MKTESTIMG(1)					      General Commands Manual						 GPIV_MKTESTIMG(1)

NAME

       gpiv_mktestimg - Generates a simplified image for image processing.

SYNOPSIS

       gpiv_mktestimg [-h | --help] [-p | --print] [-t N | --threshold N] [-w N] [-v | --version] [filename] < stdin > stdout

DESCRIPTION

       gpiv_mktestimg  generates  an  image  (pair)  in order to be processed by the processing tools. This program is provided for developing and
       testing image processing tools.

       The parameters read from the configuration resources (containing the key GPIV_IMGPROC) may be overruled by the  command	line  options,	as
       explained below.

Options
       -h | --help
	      On-line help

       -t N | --threshold N
	      Threshold value

       -v | --version
	      Print version information on standard output, then exit successfully.

       -w N   window size (default: 15)

       filename
	      Input image filename. Overrides stdin and stdout with the full filename of the image. Output will be written to filename.png. Param-
	      eters are stored in filename.par and may be used for future use by including them in ./gpivrc. If stdin and  stdout  are	used,  the
	      input is expected to be a PNG formatted image.

       SEE ALSO
	      gpivtools

AUTHOR

       Gerber Van der Graaf

								  7 November 2006						 GPIV_MKTESTIMG(1)
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