filter_create_fp(3) util/filter.h filter_create_fp(3)NAME
filter_create_fp - similar to filter_create_fd except with buffered FILE*
SYNOPSIS
#include <util/filter.h>
NEOERR *filter_create_fp(const char *cmd, FILE **in, FILE **out, FILE **err,
pid_t *pid);
ARGUMENTS
cmd -> the sub command to execute. Will be executed with
/bin/sh -c
in -> pointer to return the stdin pipe, or NULL if you don't
want the stdin pipe
out -> pointer to return the stdout pipe, or NULL if you don't
want the stdout pipe
err -> pointer to return the stderr pipe, or NULL if you don't
want the stderr pipe
DESCRIPTION
filter_create_fp is identical to filter_create_fd, except each of the pipes is wrapped in a buffered stdio FILE
RETURN VALUE
in -> the stdin FILE of the sub process
out -> the stdout FILE of the sub process
err -> the stderr FILE of the sub process
pid -> the pid of the sub process
SEE ALSO filter_wait(3), filter_create_fp(3), filter_create_fd
ClearSilver 12 July 2007 filter_create_fp(3)
Check Out this Related Man Page
p2open(3GEN) String Pattern-Matching Library Functions p2open(3GEN)NAME
p2open, p2close - open, close pipes to and from a command
SYNOPSIS
cc [ flag ... ] file ... -lgen [ library ... ]
#include <libgen.h>
int p2open(const char *cmd, FILE *fp[2]);
int p2close(FILE *fp[2]);
DESCRIPTION
p2open() forks and execs a shell running the command line pointed to by cmd. On return, fp[0] points to a FILE pointer to write the com-
mand's standard input and fp[1] points to a FILE pointer to read from the command's standard output.
In this way the program has control over the input and output of the command.
The function returns 0 if successful; otherwise, it returns -1.
p2close() is used to close the file pointers that p2open() opened. It waits for the process to terminate and returns the process status.
It returns 0 if successful; otherwise, it returns -1.
RETURN VALUES
A common problem is having too few file descriptors. p2close() returns -1 if the two file pointers are not from the same p2open().
EXAMPLES
Example 1: Example of file descriptors.
#include <stdio.h>
#include <libgen.h>
main(argc,argv)
int argc;
char **argv;
{
FILE *fp[2];
pid_t pid;
char buf[16];
pid=p2open("/usr/bin/cat", fp);
if ( pid == -1 ) {
fprintf(stderr, "p2open failed
");
exit(1);
}
write(fileno(fp[0]),"This is a test
", 16);
if(read(fileno(fp[1]), buf, 16) <=0)
fprintf(stderr, "p2open failed
");
else
write(1, buf, 16);
(void)p2close(fp);
}
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|MT-Level |Unsafe |
+-----------------------------+-----------------------------+
SEE ALSO fclose(3C), popen(3C), setbuf(3C), attributes(5)NOTES
Buffered writes on fp[0] can make it appear that the command is not listening. Judiciously placed fflush() calls or unbuffering fp[0] can
be a big help; see fclose(3C).
Many commands use buffered output when connected to a pipe. That, too, can make it appear as if things are not working.
Usage is not the same as for popen(), although it is closely related.
SunOS 5.10 29 Dec 1996 p2open(3GEN)
I have a huge matrix file containing some 1.5 million rows and 6000 columns. The matrix looks something like this:
1 2 3
4 5 6
7 8 9
3 4 5
I want to add all the numbers in the columns of this matrix and display the result to my stdout. This means that the numbers in the first column are:
... (2 Replies)
Hi,
Just trying to get to grips with sed and awk for some reporting for work and I need some assistance:
I have a file that lists policy names on the first line and then on the second line whether the policy is active or not.
Policy Name: Policy1
Active: yes
Policy... (8 Replies)
version info :
vi availabe with RHEL 5.4
I have a text file with 10,000 lines. I want to copy lines from 5000th line to 7000th and redirect to a file. Any idea how I can do this?
Note:
The above scenario is just an example. In my actual requirement, the file has 14 million lines and I want... (9 Replies)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello,
I couldn't find an actual introduction thread, so I decided to just put this here.
I go by d0wngrade online. I have been programming in multiple languages for about 15+ years. I started with standard web design languages like HTML and CSS, but I then advanced from design to development... (2 Replies)
Hi guys...
The first active code line in AudioScope.sh is set -u .
This causes a complete exit if a variable is used/found but has not been allocated at the start of the program.
However, apart from writing code to do the task, is there a switch to to check which variables have been... (17 Replies)
Hi.
In thread https://www.unix.com/shell-programming-and-scripting/267833-grouping-counting.html rovf and I had a mini-discussion on grep and awk.
Here is a demo script that compares the awk and grep approaches for this single problem:
#!/usr/bin/env bash
# @(#) s2 Demonstrate group... (1 Reply)
Hello,
I have to fish out some specific columns from a file based on the header value. I have the list of columns I need in a different file. I thought I could read in the list of headers I need,
# file with header names of required columns in required order
headers_file=$2
# read contents... (11 Replies)
For those interested in installing dash shell on OSX Lion to help test POSIX compliancy of shell scripts, it is quite easy. I did it like this:
If you don't have gcc on your system:
0. Download and install the Command Line Tools for Xcode package from Sign In - Apple *
1. Download the dash... (2 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
I have data of an excel files as given below,
file1
org1_1 1 1 2.5 100
org1_2 1 2 5.5 98
org1_3 1 3 7.2 88
file2
org2_1 1 1 2.5 100
org2_2 1 2 5.5 56
org2_3 1 3 7.2 70
I have multiple excel files as above shown.
I have to copy column 1, column 4 and paste into a new excel file as... (26 Replies)
Dear All,
Taking a break from Vue.js coding for the site, SEO and YT videos; and hopefully addressing some well deserved criticism from some here that I have been too focused on the visual aspects of the forums versus the substance and the community....
While the "current generation... (9 Replies)
Hi all...
Well guys and gals, I jumped in at the deep end and found things that PERL cannot do by default.
Many tricky terminal escape codes are not catered for so I had to create workarounds.
One thing I searched for was this:
Passing perl variable to shell command
AND, @Neo this was... (15 Replies)