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Full Discussion: Question on forks and pipes
Top Forums UNIX for Advanced & Expert Users Question on forks and pipes Post 302086930 by Phantom12345 on Monday 28th of August 2006 06:35:39 PM
Old 08-28-2006
Question on forks and pipes

I am trying to figure out why when i have the following code

int main( { printf("0\n"); fork(); printf("1\n"); exit(0);}

and type in the shell

a.out | cat

the output of this program is
0
1
0
1

instead of
0
1
1

does anyone know?
 

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PRINTF(1)								FSF								 PRINTF(1)

NAME
printf - format and print data SYNOPSIS
printf FORMAT [ARGUMENT]... printf OPTION DESCRIPTION
NOTE: your shell may have its own version of printf which will supercede the version described here. Please refer to your shell's documen- tation for details about the options it supports. Print ARGUMENT(s) according to FORMAT. --help display this help and exit --version output version information and exit FORMAT controls the output as in C printf. Interpreted sequences are: " double quote NNN character with octal value NNN (0 to 3 digits) \ backslash a alert (BEL)  backspace c produce no further output f form feed new line carriage return horizontal tab v vertical tab xNNN byte with hexadecimal value NNN (1 to 3 digits) uNNNN character with hexadecimal value NNNN (4 digits) UNNNNNNNN character with hexadecimal value NNNNNNNN (8 digits) %% a single % %b ARGUMENT as a string with `' escapes interpreted and all C format specifications ending with one of diouxXfeEgGcs, with ARGUMENTs converted to proper type first. Variable widths are han- dled. AUTHOR
Written by David MacKenzie. REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>. COPYRIGHT
Copyright (C) 2002 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU- LAR PURPOSE. SEE ALSO
The full documentation for printf is maintained as a Texinfo manual. If the info and printf programs are properly installed at your site, the command info printf should give you access to the complete manual. GNU coreutils 4.5.3 February 2003 PRINTF(1)
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