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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_uhisto

GPIV_UHISTO(1)						      General Commands Manual						    GPIV_UHISTO(1)

NAME

       gpiv_uhisto - Tests PIV data by printing/displaying an histogram of the horizontal particle displacements.

SYNOPSIS

       gpiv_uhisto [-g] [-h | --help] [-n N] [-p | --print] [-v | --version] [filename] < stdin > stdout

DESCRIPTION

       Gpiv_uhisto calculates the histogram of the horizontal particle displacement distribution between minimum and maximum values.

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

Options
       -g     Graphical visualization of the histogram with gnuplot.

       -h | --help
	      On-line help

       -n N   Override number of bins (default 10, hard coded).

       -p | --print
	      Print parameters, command line options and eventually used input and output filenames to stdout.	The output  is	identic  of  file-
	      name.par, in case -f is used.

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

       filename
	      Input  PIV  file.  Overrides stdin and stdout. Output will be written to filename.pdf. The parameters will be written or appended to
	      filename.par and may be used for future use by including them in ./gpivrc.

SEE ALSO

       gpivtools

NOTES

       stdin and stdout has still to be implemented.  [-f filename ] will be added.

AUTHOR

       Gerber Van der Graaf

BUGS

       The program seems to work fine with real PIV data.  So far, no serious bugs have been found.

								  8 November 2006						    GPIV_UHISTO(1)
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