10 More Discussions You Might Find Interesting
1. Homework & Coursework Questions
Just started learning Unix and received my first assignment recently. We haven't learned many commands and honestly, I'm stumped. I'd like to receive assistance/guidance/hints.
1. The problem statement, all variables and given/known data:
How do I write a shell script that takes in a file or... (4 Replies)
Discussion started by: fozilla
4 Replies
2. Shell Programming and Scripting
I have a program that requires the user to enter input values while it is being run
for example in bash
...
...
..
echo "Enter your input"
read input
echo $input
...
...
...I need to schedule this program with crontab, hence a problem, cronjobs run in the background, any ideas on how to... (10 Replies)
Discussion started by: walforum
10 Replies
3. Shell Programming and Scripting
Hello,
I am new to scripting.
How do I read multiple lines from the command line?
I know read reads one line, but if I have to read multiple lines, how should I do?
Thanks,
Prasanna (4 Replies)
Discussion started by: prasanna1157
4 Replies
4. UNIX for Dummies Questions & Answers
Is it possible to read from the screen or standard output? If so, may I know how I can do this?
For example, I have an application running which prints out the following on the screen:
Starting tools from .image-tools...
imagecontrol_1: SECS/GEM-capable version is running
done
cindy@pgunix... (2 Replies)
Discussion started by: sippingsoda
2 Replies
5. Shell Programming and Scripting
Hello,
Could somebody please give me an awk example on how to read from the standard input.
It means as the "read" function in Korn shell.
Thx in advance ... (3 Replies)
Discussion started by: rany1
3 Replies
6. Solaris
Please give me any example for standard input in Solaris. (6 Replies)
Discussion started by: karman0931
6 Replies
7. Shell Programming and Scripting
Hi guys,
I am new to AWK and unix scripting. Please see below my problem and let me know if anyone you can help.
I have 2 input files (example given below)
Input file 2 is a standard file (it will not change) and we have to get the name (second column after comma) from it and append it... (5 Replies)
Discussion started by: sksahu
5 Replies
8. Shell Programming and Scripting
Dear...
I have a scrpit that contains multiple read command.... when I run the script I have to enter 3 variables so that I can get the output..
but, I dont want to put those 3 inputs manually every time... I want to make a shell that reads the 3 inputs from a file.
the script name is... (4 Replies)
Discussion started by: yahyaaa
4 Replies
9. Shell Programming and Scripting
I tried copy the output files from find command into a directory.
Example,
find / -name core 2>/dev/null | xargs cp????
I have known that we can use xargs to execute command lines from standard input but how to use it in this case.
Or I can do something besides xargs. (2 Replies)
Discussion started by: lalelle
2 Replies
10. Shell Programming and Scripting
how can i redirect standard input? i dont remember :/, though could you redirec not from a command? i mean, to redirect always stdin and stout (1 Reply)
Discussion started by: Jariya
1 Replies
popen(3) Library Functions Manual popen(3)
Name
popen, pclose - initiate I/O to/from a process
Syntax
#include <stdio.h>
FILE *popen(command, type)
char *command, *type;
pclose(stream)
FILE *stream;
Description
The arguments to are pointers to null-terminated strings containing respectively a shell command line and an I/O mode, either "r" for read-
ing or "w" for writing. It creates a pipe between the calling process and the command to be executed. The value returned is a stream
pointer that can be used (as appropriate) to write to the standard input of the command or read from its standard output.
A stream opened by should be closed by which waits for the associated process to terminate and returns the exit status of the command.
Because open files are shared, a type "r" command may be used as an input filter, and a type "w" as an output filter.
Diagnostics
The routine returns a null pointer if files or processes cannot be created, or the shell cannot be accessed.
The routine returns -1 if stream is not associated with a `popened' command.
Restrictions
Buffered reading before opening an input filter may leave the standard input of that filter mispositioned. Similar problems with an output
filter may be forestalled by careful buffer flushing, for instance, with For further information, see
The routine always calls and never calls
See Also
sh(1), pipe(2), wait(2), system(3), fclose(3s), fopen(3s)
popen(3)
