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Full Discussion: Please explain this
Top Forums Shell Programming and Scripting Please explain this Post 302493384 by methyl on Wednesday 2nd of February 2011 02:09:32 PM
Old 02-02-2011
There are several problems with the line posted. We really need to see it in the context of the whole script and with a description of what the script is meant to do.

To answer one of your questions.
If there is a variable called $i which needs to be substituted into svucon$i_bal_dup_email.dat it will not work. This is because underscore is a valid character in a variable name.

Here is an example of what can happen. Note the use of braces to show shell where the variable name ends.
Code:
i=abc
echo First attempt  : $i_string
echo Second attempt : ${i}_string

First attempt :
Second attempt : abc_string

On the second point. The semi-colon is just allowing you to place two unrelated commands on the same line. It may be wrong.
The second command converts a file $dup_in to "uuencode" format outputting to $dup_out . There is no input from the preceding command.
The normal use of "uuencode" is to prepare a file to be an email attachment.
 

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LEARN ABOUT DEBIAN

unknown

UNKNOWN(1)						      General Commands Manual							UNKNOWN(1)

NAME

       unknown - identify possible genotypes for unknowns

SYNOPSIS

       A program to rapidly identify which genotypes are possible for individuals typed as unknowns in the input pedigree.

       unknown [ -cl ]

DESCRIPTION

       unknown infers possible genotypes and mating combinations for parents with unknown genotypes for ilink(1), mlink(1) and linkmap(1).

OPTIONS

       -c     Use conditional allele frequencies.

       -l     Choose a good set of loop breakers automatically.

RETURN VALUE

       0     Successful completion

ERRORS

       10    File not found
       255   Failure

EXAMPLES

       Normally, unknown(1) is run immediately prior to its sister programs, ilink(1), mlink(1) and linkmap(1), like this:

       unknown
       mlink

FILES

       unknown(1) reads the two files pedfile.dat and datafile.dat as its own input and produces various temporary files that are used as input to
       the next program. These temporary files are ipedfile.dat, upedfile.dat, speedfile.dat and newspeedfile.dat.

NOTES

       unknown(1) is part of the FASTLINK package, which is a re-implementation of the LINKAGE suite  of  computer  tools  that  help  investigate
       genetic linkage as first proposed G.M. Lathrop, J.M. Lalouel, C. Julier, and J. Ott.

AUTHORS

       Dylan Cooper, Alejandro Schaffer, and Tony Schurtz based on work originally by Jurg Ott, Ph.D, et. al.

       This manual page was written by Elizabeth Barham <lizzy@soggytrousers.net> for the Debian GNU/Linux system (but may be used by others).

WORD-WIDE-WEB
       http://www.ncbi.nlm.nih.gov/CBBResearch/Schaffer/fastlink.html

SEE ALSO

       ilink(1), linkmap(1), lodscore(1), mlink(1).

								  April 15, 2003							UNKNOWN(1)
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