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Full Discussion: question about popen in C
Top Forums Programming question about popen in C Post 302505119 by omega666 on Wednesday 16th of March 2011 09:45:28 AM
Old 03-16-2011
i tested using
Code:
    FILE *file_pointer; char output[512];     file_pointer = popen_new("ls; ls", "r");     size_t bytes = read(fileno(file_pointer), output, 512);      printf(output);     printf("%d\n", pclose_new(file_pointer));

i cant see whats wrong here


would the problem be fixed if i used write command to print the output to stdout instead of printf?

Last edited by omega666; 03-16-2011 at 10:51 AM..
 

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logprn(1)							     logtools								 logprn(1)

NAME
logprn - merge Common-Log Format web logs based on time-stamps SYNOPSIS
logprn logfile idle-time[:max-wait] command DESCRIPTION
The logprn program is designed to print new data that is appended to log files. It will wait until a specified amount of time has elapsed since the last write to the file before printing the data. It will print the data by pipeing it to a specified command. The command will be run by popen(3) so the usual shell commands will operate (whether this is a bug or a feature is a matter of opinion). OPTIONS
logfile specifies a file to read data from. It should be a regular file not a pipe, device, or anything else. idle-time max-wait command EXIT STATUS
0 Never happens, this program will run forever. 1 Bad command-line parameters or couldn't stat the log file on startup - couldn't start the program. 2 File disappeared or became unreadable at run-time. 3 Can't run the specified command. AUTHOR
This program, its manual page, and the Debian package were written by Russell Coker <russell@coker.com.au>. BUGS
Uses popen (3) but I consider this a feature not a bug. SEE ALSO
popen(3) Russell Coker <;russell@coker.com.au> 0.06 logprn(1)
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