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Top Forums UNIX for Advanced & Expert Users Help with command substitution in C program Post 302463450 by royalbull on Sunday 17th of October 2010 03:47:26 PM
Old 10-17-2010
Help with command substitution in C program

Hi,

I want to know if there's a cleaner way for assigning output of a unix command to a variable in C program .

Example : I execute dirname fname and want the output to be assigned to a variable dname . Is it possible .

I knew u can redirect the output to a file and then reread assigning it , but ca it be done in a leaner better way . Thanks in advance . Smilie
 

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mcxalter(1)							  USER COMMANDS 						       mcxalter(1)

  NAME
      mcxalter - various network transformations

  SYNOPSIS
      mcxalter [-imx <fname> (specify matrix input)] [-abc <fname> (specify label input)] [-tab <fname> (use tab file)] [-o <fname> (output)] [-tf
      spec (apply tf-spec to input matrix)]

  DESCRIPTION
      This utility supplies various transformations of networks.

  OPTIONS
      -abc <fname> (label input)
	The file name for input that is in label format.

      -imx <fname> (input matrix)
	The file name for input that is in mcl native matrix format.

      -tab <fname> (use tab file)
	This option causes the output to be printed with the labels found in the tab file.  With -abc this option will, additionally, construct  a
	graph  only on the labels found in the tab file.  If this option is used in conjunction with -imx the tab domain and the matrix domain are
	required to be identical.

      -tf <tf-spec> (transform input matrix values)
	Transform the input matrix values according to the syntax described in mcxio(5).

      -o fname (output file)
	Output file.

  AUTHOR
      Stijn van Dongen.

  SEE ALSO
      mcxio(5), mcx(1), mcxsubs(1), and mclfamily(7) for an overview of all the documentation and the utilities in the mcl family.

  mcxalter 12-068						      8 Mar 2012							 mcxalter(1)
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