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Full Discussion: two while nested loops
Top Forums Shell Programming and Scripting two while nested loops Post 302691069 by Chubler_XL on Thursday 23rd of August 2012 09:17:29 PM
Old 08-23-2012
The nested for loops are fine and are quite efficient as they are implemented within the shell. The trick here is to avoid calling the external command (nc) more times than is necessary.

As an example if you are just looking for open ports, you would gain a heap of performance by using the nc -z option and call nc once for the whole set of ports eg:

Code:
# nc -z host.example.com 25,80,5900-5910
Connection to host.example.com 25 port [tcp/smtp] succeeded!
Connection to host.example.com 5900 port [tcp/vnc] succeeded!

But, of course, this is different functionality and comes under requirements optimization, not code tweaking.
This User Gave Thanks to Chubler_XL For This Post:
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LEARN ABOUT DEBIAN

merge_fonts

merge_fonts(3alleg4)						  Allegro manual					      merge_fonts(3alleg4)

NAME

       merge_fonts - Merges two fonts into one font. Allegro game programming library.

SYNOPSIS

       #include <allegro.h>

       FONT *merge_fonts(FONT *f1, FONT *f2)

DESCRIPTION

       This function merges the character ranges from two fonts and returns a new font containing all characters in the old fonts. In general, you
       cannot merge fonts of different types (eg, TrueType fonts and bitmapped fonts), but as a special case, this function can  promote  a  mono-
       chrome bitmapped font to a color font and merge those. Example:

	  FONT *myfont;
	  FONT *myfancy_font;
	  FONT *lower_range;
	  FONT *upper_range;
	  FONT *capitals;
	  FONT *combined_font;
	  FONT *tempfont;
	  ...
	  /* Create a font that contains the capitals from  */
	  /* the fancy font but other characters from myfont */
	  lower_range = extract_font_range(myfont, -1, 'A'-1);
	  upper_range = extract_font_range(myfont, 'Z'+1, -1);
	  capitals = extract_font_range(myfancy_font, 'A', 'Z');

	  tempfont = merge_fonts(lower_range, capitals);
	  combined_font = merge_fonts(tempfont, upper_range);

	  /* Clean up temporary fonts */
	  destroy_font(lower_range);
	  destroy_font(upper_range);
	  destroy_font(capitals);
	  destroy_font(tempfont);

RETURN VALUE

       Returns a pointer to the new font or NULL on error. Remember that you are responsible for destroying the font when you are finished with it
       to avoid memory leaks.

SEE ALSO

       extract_font_range(3alleg4), is_trans_font(3alleg4), is_color_font(3alleg4), is_mono_font(3alleg4), exfont(3alleg4)

Allegro 							   version 4.4.2					      merge_fonts(3alleg4)
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