#include <stdio.h>
#include <unistd.h>
void main()
{
int pid, pipefd[2], parentpid, childpid;
parentpid=getpid();
pipe(pipefd);
if (pid=fork()) {
printf("I am the parent process and my pid is %d\n", getpid());
printf("My child process has a pid of %d\n", pid);
read(pipefd[0], (char *) &childpid, sizeof(childpid));
printf("My child process sent me %d\n", childpid);
} else {
childpid=getpid();
printf("I am the child and my pid is %d\n", childpid);
write(pipefd[1], (char *) &childpid, sizeof(childpid));
exit(0);
}
printf("I am still the parent process and my pid is %d\n", getpid());
exit(0);
}
A broken pipe means that you are writing onto a pipe that has been closed by the other end.
Hi
I tried to open the man page of sh and piped to `pg`. Normally while reading a file page by page using `pg`, if we wanna quit at the middle of file, we give "q" near the colon mode.
Ex1: $cat file1 | pg
hi
how
r
u
: (page1) now press "return key", it will go to next page
yes
i ... (1 Reply)
Hi
I tried to open the man page of sh and piped to `pg`. Normally while reading a file page by page using `pg`, if we wanna quit at the middle of file, we give "q" near the colon mode.
Ex1: $cat file1 | pg
hi
how
r
u
: (page1) now press "return key", it will go to next page
yes
i ... (3 Replies)
hi guys, o have a big error
in this program but i cant solve
someone ?!
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
int main(int argc, char *argv){
int cont = 2, posicao;
char geraArquivo= "|cat>>", espaco=" ";
char nomeArquivo, comando,... (11 Replies)
Hi, guys:
I am working on my shell using c. How can I use pipe to implement the following?
ls -l 1>> | grep hellp 1<< 2>> | less 2<<
(the output of ls goes to grep, and the output of grep goes to less)
Thanks
Please use and tags when posting code, data or logs etc. to preserve... (1 Reply)
I want to do the following in perl:
print $output | grep ' something' | awk '{print $2}';
I know there is system(); but it does not behave the way I was expecting it in perl. (2 Replies)
Hi guys.
I've a problem with pipes, I'm trying to make a program that can create a child process and they must generate the folowing output:
Ping ... Pong
Ping ... Pong
Ping ... Pong
I want syncronize the output whithout using the semephores, can anyone help me?
Thanks in advance.
/**
*... (1 Reply)
Hi all,
I would like to use properly an input pipe, like this :
cat myFile.txt | myCommand.shI always find this solution :
while read line; do ...; donebut I have a great lost of performance !
On a big file, with a simple grep, I can spend 2400 times more time ! oO
(from 0,023sec to 1m)... (4 Replies)
Hi guys,
I need to know how i can ignore Pipe '|' if Pipe is coming as a column in Pipe delimited file
for eg:
file 1:
xx|yy|"xyz|zzz"|zzz|12...
using below awk command
awk 'BEGIN {FS=OFS="|" } print $3
i would get xyz
But i want as :
xyz|zzz to consider as whole column... (13 Replies)
Discussion started by: rohit_shinez
13 Replies
LEARN ABOUT ULTRIX
vsprintf
vprintf(3int)vprintf(3int)Name
vprintf, vfprintf, vsprintf - print formatted output of a varargs argument list
Syntax
#include <stdio.h>
#include <varargs.h>
int vprintf ( format, ap )
char *format;
va list ap;
int vfprintf ( stream, format, ap )
FILE *stream;
char *format;
va list ap;
int vsprintf ( s, format, ap )
char *s, *format;
va list ap;
Description
The international functions and are similar to the standard I/O functions.
Likewise, the vprintf functions are similar to the printf functions except they are called with an argument list as defined by instead of
with a variable number of arguments.
The international functions allow you to use the %digit$ conversion character in place of the % character you use in the standard I/O
functions. The digit is a decimal digit n from 1 to 9. The international functions apply conversions to the nth argument in the argument
list, rather than to the next unused argument.
You can use the % conversion character in the international functions. However, you cannot mix the % conversion character with the %digit$
conversion character in a single call.
You can indicate a field width or precision by an asterisk (*) instead of a digit string in format strings containing the % conversion
character. If you use an asterisk, you can supply an integer arg that specifies the field width or precision. In format strings containing
the %digit$ conversion character, you can indicate field width or precision by the sequence *digit$. You use a decimal digit from 1 to 9
to indicate which argument contains an integer that specifies the field width or precision.
The conversion characters and their meanings are identical to
You must use each digit argument at least once.
Examples
#include <stdio.h>
#include <varargs.h>
main()
{
char *function_name = "vpr";
char *arg1 = "hello world";
int arg2 = 2;
char *arg3 = "study";
char *i18nfmt = "%1$s %3$d
";
test(function_name, i18nfmt, arg1, arg2, arg3);
}
test(va_alist)
va_dcl
{
va_list args;
char *fmt;
char string[1024];
va_start(args);
(void)printf("function %s: ", va_arg(args, char *));
fmt = va_arg(args, char *);
(void)vprintf(fmt, args);
va_end(args);
}
See Alsosetlocale(3), scanf(3int), printf(3s), printf(3int), vprintf(3s), putc(3s), scanf(3s), stdio(3s), varargs(3)
Guide to Developing International Software
vprintf(3int)