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Wow, that was it. I'm happy to hear that because I thought it should end up with a system call anyway.
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<div style="LINE-HEIGHT: 15pt">Then isn't there some codes making the system call? Or is it that the compiler understands that 'write' is a system call and inserts the assembly code for calling it by itself?</div>
<div style="LINE-HEIGHT: 15pt">Thanks in adv.</div>
<div style="LINE-HEIGHT: 15pt">Chan<br>
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<div style="LINE-HEIGHT: 15pt"><b>From : </b>"Mohan L" <l.mohanphy@gmail.com><br>
<b>Sent : </b>2014-03-12 15:31:24 ( +09:00 )<br>
<b>To : </b>Kim Chan <ckim@etri.re.kr><br>
<b>Cc : </b>Dave Hylands <dhylands@gmail.com>, kernelnewbies@kernelnewbies.org <kernelnewbies@kernelnewbies.org><br>
<b>Subject : </b>Re: where is the printf source for busybox?<br>
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<div style="LINE-HEIGHT: 15pt">ssize_t attribute_hidden _cs_write(void *cookie, const char *buf, size_t bufsize)<br>
{<br>
return write(*((int *) cookie), (char *) buf, bufsize);<br>
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<div style="LINE-HEIGHT: 15pt">what does cs stand for here? (Hm.. seems like custom streams..in the code) and I couldn't follow past write above. Where is the function write defined?
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Hi Chan,</div>
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write is a system call.</div>
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$ man 2 write</div>
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<div class="gmail_default"><font face="courier new, monospace">syscall table for x86 architecture can be found in : </font><span style="FONT-FAMILY: 'courier new',monospace"> </span><span style="FONT-FAMILY: 'courier new',monospace"><path>/arch/x86/syscalls/syscall_32.tbl</span><br>
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<div class="gmail_default"><font face="courier new, monospace"># cat <path>/arch/x86/syscalls/syscall_32.tbl | grep 'write'</font></div>
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<div class="gmail_default"><span style="FONT-FAMILY: 'courier new',monospace">4 i386 write sys_write</span><br>
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<div class="gmail_default"><span style="FONT-FAMILY: 'courier new',monospace">The format is:</span><br>
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<div class="gmail_default"><font face="courier new, monospace"><number> <abi> <name> <entry point> <compat entry point></font><span style="FONT-FAMILY: 'courier new',monospace; FONT-SIZE: small"></span></div>
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<div class="gmail_default"><font face="courier new, monospace">search sys_write definition in kernel source.</font><br>
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<div class="gmail_default"><font face="courier new, monospace">Thanks</font></div>
<div class="gmail_default"><font face="courier new, monospace">Mohan L</font></div>
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