@dircategory Text creation and manipulation
@direntry
* sed: (sed).                   Stream EDitor.

@end direntry

@clear PERL
@set SSEDEXT GNU extensions
@set SSED GNU @command{sed}

@c Ugly hack to enable using new texinfo commands '@codequotebacktick'
@c and '@codequoteundirected' or define empty fallbacks if they are
@c not available.

@ifclear txicommandconditionals
@c If we got here, this is a REALLY old texinfo (pre 5.0),
@c and '@ifcommandnotdefined' is not defined.
@c Assume these commands are not defined as well.
@macro codequotebacktick
@end macro
@macro codequoteundirected
@end macro
@end ifclear

@ifset txicommandconditionals
@c if we got here, this texinfo supports checking for defined
@c commands. If these commands aren't available - define empty
@c fallbacks.
@ifcommandnotdefined codequotebacktick
@macro codequotebacktick
@end macro
@macro codequoteundirected
@end macro
@end ifcommandnotdefined
@end ifset


@c define variables that will render as characters
@c on both HTML (with @U{}) and PDF (with greek symbols).
@c Use with: @value{ucsigma}
@c
@c Based on:
@c https://lists.gnu.org/archive/html/help-texinfo/2012-06/msg00004.html
@iftex
@set ucsigma @math{@Sigma{}}
@end iftex
@ifnottex
@set ucsigma @U{03A3}
@end ifnottex

@iftex
@set lcsigma @math{@sigma{}}
@end iftex
@ifnottex
@set lcsigma @U{03C3}
@end ifnottex

@c Unicode Replacement Character (U+FFFD):
@c no easy/portable tex equivalent, so use another
@c distinct symbol (which will be rendered very differently
@c than ascii characters in @examples.
@iftex
@set unicodeFFFD @math{@otimes{}}
@end iftex
@ifnottex
@set unicodeFFFD @U{FFFD}
@end ifnottex