Login or Register to Ask a Question and Join Our Community


Programming

Print C file output both in stdout and file

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Programming Print C file output both in stdout and file
# 8  
Old 11-14-2008
To my knowledge, you can't have one file descriptor going to multiple files. Something, somewhere has to make a second write.

Also, please put code in code tags, like this:
Code:
int main(void) { return(0); }

Quote my message to see how code tags work.
# 9  
Old 11-14-2008
Quote:
Originally Posted by nicos
I want to print the result of execve sys call (the output of the program), both in stdout and in a file without the need to execute it twice?
thanxSmilie
So what you need to do is to pipe the output of the exec call back to the calling process. The calling process will read the output of the exec call and call print/write for each file-descriptor you want to write to. You can, alternatively, fork/exec a tee process, and join the output of your execve call (above) into the input of the tee process.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Output of until to file versus stdout

Why does this until false; do history | head -5; done result in a stdout infinite loop, yet until false; do history | head -5 > hist5; done only writes it once to file hist5? Furthermore, I can hear the hard drive working on the 2nd command until I end the process, but the history | head -5 is... (1 Reply)
Discussion started by: Xubuntu56
1 Replies

2. Shell Programming and Scripting

Print the output with different file names

I have a python script that gives output called test.png. By using the following command I run the script every 2 seconds. What is the easiest way to save the output as follows ( test.png (1st output), tes1.png (second output), tes2.png ....) Command I i use while sleep 2; do python... (1 Reply)
Discussion started by: quincyjones
1 Replies

3. Shell Programming and Scripting

Run a program-print parameters to output file-replace op file contents with max 4th col

Hi Friends, This is the only solution to my task. So, any help is highly appreciated. I have a file cat input1.bed chr1 100 200 abc chr1 120 300 def chr1 145 226 ghi chr2 567 600 unix Now, I have another file by name input2.bed (This file is a binary file not readable by the... (7 Replies)
Discussion started by: jacobs.smith
7 Replies

4. Shell Programming and Scripting

File descriptors, redirecting output, and stdout

Hello all. I've been lurking here for a year or two and finally decided to post. I need some assistance with file descriptors, stdout, and redirecting output. I've searched through a number of very helpful threads here (unfortunately I can't link to any of them yet due to my low post count...),... (2 Replies)
Discussion started by: Michael_K
2 Replies

5. Shell Programming and Scripting

Awk script to run a sql and print the output to an output file

Hi All, I have around 900 Select Sql's which I would like to run in an awk script and print the output of those sql's in an txt file. Can you anyone pls let me know how do I do it and execute the awk script? Thanks. (4 Replies)
Discussion started by: adept
4 Replies

6. Shell Programming and Scripting

Print to both file and stdout

Using echo command, send output to both places. I think I knew this but forgot. Thanks in advance (2 Replies)
Discussion started by: stevensw
2 Replies

7. Shell Programming and Scripting

Print permissions for a file in output

hi i m trying to print the permissions for a file in output echo name read name touch name.txt permission=$((ls -l $name.txt)) echo permission please suggest where i went wrong? (2 Replies)
Discussion started by: angel12345
2 Replies

8. Shell Programming and Scripting

print out a line from a output file

I am trying to have a script ping all the clients then output it to a file so I know which clients are off then have the next script pull the ones that are online and reboot them. This is what I am running with right now. If there is something KISS then by all means please let me know. ... (3 Replies)
Discussion started by: deaconf19
3 Replies

9. Shell Programming and Scripting

let curl output to stdout AND save to a file

hello hackers. i have a curl process running as cgi directly pushing stdout to the client. but i want to additionally save that stream to a file at the same time. any directions madly welcome. thanks in advance (3 Replies)
Discussion started by: scarfake
3 Replies

10. Shell Programming and Scripting

Dual output (stdout and file)

Hello everybody, Is there a more elegant way to make dual output (display on standard output and append to a file) while I'm executing a shell script, besides duplicating the echo command for every string? echo "Message..." > 1 echo "Message..." >> myfile.out Thank you for your time,... (2 Replies)
Discussion started by: AdrianM
2 Replies
Login or Register to Ask a Question