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Full Discussion: question about popen in C
Top Forums Programming question about popen in C Post 302505196 by omega666 on Wednesday 16th of March 2011 12:15:41 PM
Old 03-16-2011
ok i changed it to fread and fwrite and it works now.

also if i change a value of a file pointer array to 0, and then if it gets compared to a NULL value will it crash? or should i just change it to a NULL value.

also when testing when i changed all the fread/fwrite amount to 1000 for maximum bytes used, i get errors like
/bin/sh: hdü·ls: not found

but if i keep it to like 512 it works fine, why is this?

also can you explain again why the command "ls; ls" prints the files line by line for each filename and not all in a line?

if i do fwrite, i get the output like

___ ___ ___ ___
___ ___ ___ ___

but otherwise when the execl command runs the output is like
___
___
___
___
___
etc

Last edited by omega666; 03-16-2011 at 01:46 PM..
 

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NETSNMP_TRAP_API(3)						     Net-SNMP						       NETSNMP_TRAP_API(3)

NAME
send_easy_trap, send_trap_vars, send_v2trap - send TRAPs or INFORMs from a Net-SNMP MIB module SYNOPSIS
#include <net-snmp/agent/agent_trap.h> void send_easy_trap(int trap, int specific); void send_trap_vars(int trap, int specific, struct variable_list *vars); void send_v2trap(struct variable_list *vars); DESCRIPTION
These three routines may be used to send traps from a MIB module within the Net-SNMP agent (including an AgentX subagent). send_easy_trap() sends an SNMPv1 trap (or the SNMPv2 equivalent) to the list of configured trap destinations (or "sinks"), using the pro- vided values for the generic trap type, and specific trap value. send_trap_vars() is similar, but appends the supplied list of variable bindings to the traps that are sent. send_v2trap() uses the supplied list of variable bindings to form an SNMPv2 trap, which is sent to SNMPv2-capable sinks on the configured list. An equivalent INFORM is sent to the configuredq list of inform sinks. Sinks that can only handle SNMPv1 traps are skipped. The various "send_trap()" calls allow you to specify traps in different formats. And the various "trapsink" directives allow you to spec- ify destinations to receive different formats. But *all* traps are sent to *all* destinations, regardless of how they were specified. I.e. it's ___ trapsink / send_easy_trap ___ [ Trap ] ____ trap2sink ___ [ Generator ] send_v2trap / [ ] ----- informsink ____ trapsess *Not* send_easy_trap -------------------> trapsink send_v2trap -------------------> trap2sink ???? -------------------> informsink ???? -------------------> trapsess WARNINGS
These routines are used to send the traps immediately they are called. Invoking them at the appropriate time is left to the MIB module programmer. SEE ALSO
snmpd.conf(5), snmptrapd(8) V5.7.2 13 Aug 2010 NETSNMP_TRAP_API(3)
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